He was born at Hanging Heaton near Dewsbury in the old West Riding of Yorkshire. He was educated in Batley and lived at Ossett near Wakefield. He will however always be associated with Runswick Bay on the coast of North Yorkshire where he and his family spent many holidays at the house he built in 1919.

Senior completed his Art training at the Wakefield College of Art, and the Slade School of Art, under Alphonse Legros. He became a member of the British Impressionist Group of Painters, who drew inspiration from the French 'En Plein Air'. They painted with vibrant colors and with fleeting impressions of the natural world and the people in it. Senior is most remembered for his portrayal of the fishing community of Runswick and Staithes. His contemporaries were, Gilbert Foster, Harold and Dame Laura Knight, Frederick William Jackson, James William Booth (Who was Senior's pupil) Owen Bowen, Arthur Friedenson, Frederick William Mayor, Charles Mackie, and Roland Henry Hill who said of Senior,' he was one of the men for whom everybody had a great deal of affection and he regularly helped his fellow painters in a practical way'.

A bronze bust was modeled and cast of Senior by his friend and fellow artist, Sir Frank Brangwyn.

Exhibition:
Catalogue 16th April-2nd July' 1983, held at the Wakefield City Art Gallery, Foreword written by, Gillian Spencer.