In making this painting McKenna was very aware of the importance of the oak tree as an English national symbol, and of pictures of single trees by other artists such as Courbet, Crome and Caspar David Friedrich. The artist made drawings of a particular oak tree in Dulwich Park, south London, and developed the painting from them. The landscape background is imaginary. 'An English Oak Tree' is a pair with one of a beech tree in a large park in Brussels, painted at the same time. McKenna has painted several pictures of city parks, being interested in their combination of the natural and the man-made.