On March 21, 1921, Irish Volunteers of the Kerry No. 2 Brigade ambushed a train at Headford, County Kerry. It would be the largest battle of the war in Kerry. Just a few months earlier, such a large ambush in Co. Kerry would have been totally unexpected. In Dublin, as 1920 ended, the GHQ considered Kerry to be one of the counties that was not taking the fight to the enemy as vigorously as possible. Early in the independence movement, the county had appeared to be one of the leaders in the fight. But as March began, Kerry No. 2 had formed a flying column and were ready to turn up the pressure on the Crown forces in Kerry.