On December 4, 1929, in the offices of Stanberry Superintendent L.A. Zelliff, several schools met to form an athletic conference in Northwest Missouri. The conference was established to schedule football and basketball games and track meets to help cut down on travel expenses. Other goals of the conference were to increase interest among the member schools and increase gate receipts.

By December 6, King City, Stanberry, Maysville and Bethany had paid for the membership fee of $2. Grant City had signified their interest and Albany was also being considered. The conference named F.E. Patrick of Bethany as their first president, and R.H. Watson of King City as their first secretary-treasurer.

By January of the next year, Grant City and Albany had joined, but the conference was still without a name. Princeton also applied for admission at the time but was denied due to travel concerns and conditions of the roads in those days. The naming of the conference was left to students of the six schools. The name “Grand River Six” was selected. The name was chosen over “Grand River Valley Conference”, “Grand River Conference”, “Blue Grass Conference”, “Northwest Six”, “Little Six”, “Big Six”, “Small Six”, “Quad County Six”, “Pine to Palm Conference”, “Athletic Six” and “Ever Ready Conference”.

The first athletic event of the new Grand River Six was originally scheduled to be a basketball tournament at King City. At a meeting of the members in Stanberry on January 25, 1930, drawings for the first tournament were conducted. Albany and Bethany were scheduled to compete in the first ever competition of the Grand River Six on Friday, February 21, 1930 followed by Maysville and Stanberry. However, the tournament ended up being canceled due to a conflict with sub-districts in Albany.

The original ticket prices were to be 25 cents for students the first-round and semi-final games and 35 cents for the finals. Admission for adults were to be 35 cents and 50 cents respectively.

On March 15, 1930, the members of the conference decided to hold the first track, field and golf meet on April 11. The track meet was held at the Fairgrounds in Bethany. Each school was permitted to enter two men in each event. Maysville won the track meet with 56.5 points and Maysville finished second with 53.5 points. Donald Thrailkill of Albany won the Golf tournament with a score of 85.

On April 17, 1930, the conference set the first ever football schedule. The first games were played on Friday, October 3, 1930. Albany traveled to Stanberry and King City played at Grant City in the first conference football games. Due to Maysville having a non-conference game scheduled on October 3, Bethany and Maysville did not play their first conference game until October 10. Bethany and Maysville ended up playing on Thanksgiving Day for the conference championship. Bethany defeated Maysville 18-6. Maysville led 6-0 going into the fourth quarter before Bethany scored three touchdowns to win.

On September 25, 1930, the conference scheduled its first ever regular-season basketball games for the 1930-1931 school year. Bethany traveled to King City on December 12, 1930 for the first conference game. Maysville won the first conference championship in basketball with a record of 9-1.

The conference started out as the Grand River Six, but it would not stay at six teams for long. With additions (and subtractions) to the conference and the number of teams changing over time, people would start to refer to the conference simply as the Grand River Conference or the GRC.

The first change in the conference occurred in 1933. In September 1933, Maysville had just graduated most of their conference championship team from the year before. Coach Lon Wilson of Maysville was hesitant about “fielding a team of green timber.” As a result, Maysville decided to cancel all of their conference games for the 1933 season. There were some that believed that Maysville cancelled their games due to not having a championship caliber team; however, others stated that they simply did not have boys big enough to play football at all “except at great risk to their limbs and their lives.” During their meetings on October 18, the conference dropped Maysville as a member of the conference. Originally, the sentiment was to just suspend Maysville, but the other members ultimately voted to eject Maysville from the conference. The conference wasted no time in finding a replacement for Maysville. The conference invited Conception College to take the place of Maysville. The conference would be back at six teams. Conception formally accepted the invitation on March 12, 1934 in time to play in the conference’s first baseball season. Conception would win the Grand River Conference baseball championship in its first season.

It didn’t take long for the Maysville and the rest of the conference to make amends. On February 25, 1935, the conference voted to allow Maysville back in the conference. For the first time, the Grand River Conference would have seven teams. On March 16, 1936, the GRC expanded to eight teams by inviting Ridgeway. Savannah also applied for admission, but was not invited. The eight-team conference would not last long. In June of 1936, Conception notified the conference that they had decided to withdraw after only a little over two years in the conference. Alumni and faculty of Conception were concerned about the travel and wanted to play teams in towns closer to them. Conception College’s tenure in the GRC was the shortest of any school in its history.

On September 12, 1938, Princeton once again applied for membership into the Grand River Conference. This time, they were admitted unanimously. They began play in the GRC starting with the 1938-39 basketball season marking the first time that the conference officially competed as an eight-team conference. Princeton’s entry in the GRC marked the 6th change in member ship in six years for the conference. However, after Princeton joined, the conference would remain stable for the next nine years.

In November of 1946, Gallatin was invited to join the conference increasing the membership in the conference to nine teams. Gallatin’s first GRC event was at the 1947 Track and Field Meet. In 1948, Ridgeway decided to withdraw from the conference and Hamilton was accepted as a replacement for them. Hamilton had already completed their football schedule so their first competition in the GRC was in basketball.

In March of 1955, Cameron was invited to join the Grand River Conference increasing the membership to ten teams. Due to two-year game contracts already made by GRC schools, Cameron would not become an official member of the conference until July of 1957. Cameron won the GRC football championship in its first season. When Cameron joined, there were some in the conference that felt that Cameron was too big for the GRC, and that the others would not be able to compete against them in football. An editorial in The Stanberry Highlight wrote “Cameron was voted into the conference by various officials of the Grand River Conference. Cameron is not to blame for what happened, but one thing is for certain-as long as Cameron high school is in the conference there probably will be a lot of second, third and fourth place teams with never a hope for a conference championship. It’s a bit like Oklahoma in the now Big Eight conference.” Cameron’s time in the GRC would only last 15 years. In 1971, they announced that they would be leaving the conference to join the Midland Empire Conference beginning with the 1972-1973 school year. Cameron’s main motivation for moving out of the conference was due to playing a schedule of smaller schools that hurt their chances of advancing to the Missouri high school football playoffs.

After Cameron’s exit in 1972, the conference would not drop or add any full members again until 2006. However, it would still go through multiple changes. In 1988, 5 schools from the nearby Highway 275 Conference moved from 11-man football to 8-man football, leaving Rock Port and Tarkio as the only two schools in the 275 Conference still playing 11-man. This led to several football-only changes in the Grand River Conference that impacted area schools over the next 20+ years. In 1989, Worth County was unable to field an 11-man team; therefore, they had to switch to 8-man. As a consequence, their football games were forfeited while they played an 8-man schedule. In 1990, Stanberry, switched to 8-man also. Worth County and Stanberry would schedule teams from area conferences while still being a member of the GRC. Due to the large number of teams moving to 8-man, those four schools were left trying to put together football schedules without the help of a conference schedule. As a result, starting with the 1992 football season, Worth County and Stanberry joined the Highway 275 Conference and Rock Port and Tarkio joined the GRC as football-only members. They each would retain full membership in their respective conferences for all other sports. At the same time, King City made the decision to switch to 8-man and also joined the Highway 275 Conference for football only.

On November 13, 2003, Rock Port became the second school in conference history to be dropped from the conference by the membership. The nine full members voted unanimously to oust Rock Port due, in part, to an issue resulting from an October 10 football game that was never played because the game officials never showed up. Hamilton Superintendent, David Fairchild, said that not playing the game was not the overriding factor in the decision, however. Location was another factor. According to the St. Joseph News-Press, Rock Port had traveled to play South Harrison for the game on October 10. Both teams had warmed up and were ready to play, but the officials had not shown up. The problem is that they had been double-booked due to an error by Rock Port. MSHSAA officials told the schools that they had four choices. They could wait until officials were available later that night, play the game on Saturday, play the game on Monday or deem the game a no-contest. Rock Port chose the fourth option. South Harrison offered to play on Saturday or Monday. In addition, they offered to travel to Rock Port which Rock Port refused due to conflicts with other activities. The conference also voted on whether to retain Tarkio which passed by a vote of 7-2. According to Fairchild, “Tarkio played their football games. Tarkio was in good standing with the conference.”

In December of 2005, the GRC added a full-member to the conference for the first time in 50 years when Polo became a member of the Grand River Conference, starting with the 2006-07 school year, increasing the full membership to ten teams. Polo had previously applied for membership in 2003, but was not invited at that time. In addition to Polo joining, King City switched back from 8-man to 11-man in football, so the GRC would have nine teams in football. On October 22, 2009, Tarkio made the decision to switch from 11-man to 8-man starting with the 2010 football season. The move would mark the end of the GRC having football-only members.

On April 21, 2011, Hamilton was accepted as a member of the KCI Conference and decided to depart the Grand River Conference starting with the 2012-13 school year. They were the first full member to leave the conference in 39 years. Braymer replaced Hamilton to keep the conference at ten full members. Albany moved to 8-man football and played in the 275 Conference for football only starting with the 2014 season leaving the only 7 schools left playing 11-man.

For the first time in its history, the GRC added more than one full member at the same time when they added six new members in 2015. St. Joseph Christian, Trenton, North Andrew, Pattonsburg, Putnam County and Milan all accepted invitations into the conference and started competing during the 2016-17 school year.

With the addition of six new schools, the Grand River Conference became the largest conference in Northwest Missouri with 16 schools. On February 6, 2015, the conference announced the addition of four of the schools: North Andrew, Pattonsburg, St. Joseph Christian and Trenton. Since all of the schools except Trenton played 8-man football at the time, this allowed the GRC to now have divisions for both 8-man and 11-man becoming Missouri’s only conference to have both. The move allowed the three existing schools playing 8-man (Albany, Stanberry and Worth County) to once again play football in the conference.

However, the GRC was not done expanding. On February 18, Milan became the 15th school in the conference. Putnam County would accept a bid one day later to become the 16th school. Having 16 schools would present some logistical challenges. First, there were 10 11-man football teams and 6 8-man football teams. However, King City and Braymer made the decision to switch to 8-man beginning with the 2016 season. With those two teams moving to 8-man, the GRC now had half of its teams playing 8-man and half of them playing 11-man. The divisional splits in football also were closely aligned with geography, so the conference made the decision to use the same splits for both basketball and softball. The schools that played 8-man would be the Western Division in those two sports while the 11-man teams would comprise the Eastern Division. The only exception was St. Joseph Christian who did not field a softball team.

In basketball and softball, only games against teams in the division would count in the conference standings, but teams were encouraged to schedule conference opponents from the other division. At the end of the season, inter-division games were played against teams from the other division as determined by the division standings. Games were played at the western sites for softball and eastern sites for basketball the first year and then switched. The conference also started championship events for golf, wrestling and track and field.

During the 2018-19 basketball season, instead of playing inter-division games at each school, the conference hosted all 16 schools at the same location the same day in an event called the Grand River Conference Showcase. All 16 schools met at South Harrison on February 9, 2019. Seven games were played on the junior high court and nine games were played high school court including both boys and girls championship games. The schools would meet again on February 15, 2020 at King City with eight games on each court. The 2021 Showcase was cancelled due to COVID-19 and the games were played at Eastern Division schools. The Showcase returned to a single location again in 2022 in Milan.

At the time the conference expanded to 16 teams, only three schools had baseball, Braymer, Milan and Putnam County. Over the next few years, other schools in the conference would start adding baseball. By the 2019 season, the conference had expanded to 10 baseball teams and would play a conference schedule. Albany and Princeton added baseball teams in 2020 to expand the conference to 12 baseball teams. However, due to COVID-19, all 2020 spring sports, inluding baseball, were cancelled. Polo would add baseball for the 2023 season to bring the number of teams playing a conference schedule to 13.

On February 4, 2019, St. Joseph Christian announced that they would be forming a co-op with Northland Christian for football. As a result, St. Joseph Christian switched from 8-man to 11-man. However, after two seasons, they made the decision to end the co-op and return to 8-man for the 2021 season.

On December 12, 2019, Braymer announced that they were leaving the Grand River Conference for the 2020-21 school year. The conference announced on October 23, 2020, that North Harrison would replace Braymer to bring the number of members back to 16. North Harrison began competition in the GRC starting in the 2021-22 school year.

On November 15, 2022, Princeton voted to move from 11-man to 8-man football. They started play in the GRC West for the 2023-24 school year.

On December 19, 2022, Marceline accepted an invitation to join the Grand River Conference. The following day, Brookfield accepted an invitation to join. The will be start play in the GRC for the 2024-25 school year.

On March 2, 2023, Superintendents of the GRC Schools voted by a count of 12-4 to split the conference into two separate conferences beginning with the 2023-24 school year. The dissenting votes were cast by Maysville, Polo, Putnam County and South Harrison. The two conferences form along the divisional lines that were already established for the 2023-24 school year which includes Albany, King City, North Andrew, North Harrison, Pattonsburg, Princeton, St. Joseph Christian, Stanberry and Worth County in one of the conferences. The other conference consists of Gallatin, Maysville, Milan, Polo, Putnam County, South Harrison and Trenton in 2023-24 with Brookfield and Marceline joining in 2024-25. The official names of the conferences are Grand River Conference for the former East Division schools (except Princeton) and Grand River Conference West for the former West Division schools plus Princeton.

During the 2023-24 season, Marceline competed as an affiliate member of the GRC for Girls Golf, and Brookfield and Marceline competed as affiliate members for Wrestling and Boys Golf before becoming full members in 2024-25. East Atchison and Rock Port joined as affiliate members of the GRC West for Wrestling starting in the 2023-24 school year.