The Counties Athletic Union was formed at a meeting of the County Associations Executive Committee held at the offices of the AAA on 4 Feb 1926. This followed a decision by the General Committee of the AAA not to take over the Inter-County Championships, which had been held for the first time, organised by the Counties Associations Committee, held on Saturday 22 August 1925 at Stamford Bridge, London, under the auspices of the AAA.

The AAA Committee had recommended in 1918 that County Associations should be set up to promote athletics in each county. The County Associations Committee of the AAA held its first meeting on 25 Sep 1923 and at their April 1925 meeting agreed the staging of an Inter-County Relay Contest.

In November 1925 a meeting was held in the Offices of the AAA with delegates representing Buckinghamshire, Hertfordshire, Kent, Middlesex, Surrey, Sussex, Wiltshire, Norfolk and Suffolk. It was proposed that the County Associations were the proper body to be entrusted with the promotion of an Inter County Championship. The General Committee of the Amateur Athletic Association raised no objections and had minuted at one of their meetings that representatives of County Associations are the proper body to be entrusted with the promotion of an Inter County Meeting.

The 4 February 1926 meeting was attended by delegates from Buckinghamshire, Cambridgeshire, Essex, Hertfordshire, Kent, Middlesex, Norfolk, Suffolk, Surrey and Sussex. Letters of apology were received from Hampshire, Wiltshire and several County Associations in the Midlands and the North who were unable to attend the meeting, but nevertheless were in interested in the movement. This meeting also endorsed the staging of the first Inter County Cross Country Championship held at Beaconsfield on Saturday 3 April 1926.

The first CAU meeting was held at the Olde Rectory, Beaconsfield on 3 April 1926. This was attended by representatives of 14 counties: Bedfordshire, Buckinghamshire, Cambridgeshire, Essex, Gloucestershire, Hampshire, Hertfordshire, Kent, Middlesex, Staffordshire, Surrey, Sussex, Wiltshire and Worcestershire and they approved the Union’s Constitution.

The initial Constitution stated that: “The objects of the Union are to encourage and foster the development of the County Spirit in Amateur Athletics, especially by the promotion of an Inter-County Team and Relay Championship Meeting, and an Inter-County Cross Country Team Championship; and by encouraging Team competitions between the Counties.”

The initial subscription was fixed at 10/6d annually. 18 counties were members in the first year, 1926. 

At an Extraordinary General Meeting held in Corby on Monday 25 May 1992, the Counties Athletic Union was dissolved, being replaced by the newly established UK Counties Athletic Union. At the same meeting a new constitution was formally adopted.

From their inception in 1925 through to the late sixties, apart from the war years 1940-6, the CAU Inter County Track & Field Championships were a major international fixture held annually at the end of May, on what was then known as the Whitsun Bank Holiday. After spells at the White City, Crystal Palace, Warley, Leicester, Birmingham and Corby, the event has been regularly staged in Bedford.

The Inter Counties Cross Country equally became a major fixture in the athletic calendar and today still plays an important role in endurance running, providing a high standard of competition for U13, U15, U17, U20 and senior athletes.