Leader was born in Worcester as Benjamin Leader Williams, the son, and first child of eleven children, of notable civil engineer Edward Leader Williams (1802–79) and Sarah Whiting (1801–88). His father was described as a "non conformist dissenter" and his mother was a Quaker – their marriage in an Anglican church resulted in them being disowned by the Society of Friends. In 1857 he changed his name to Benjamin Williams Leader to distinguish himself from the many other painters with the surname Williams. Leader's early works bore the influence of the Pre-Raphaelites with their attention to fine detail and emphasis on painting from nature "en plein air". In his later years he adopted a looser style which was more impressionistic rather than being an exact copy of nature and this proved to be more popular.