[2] His father, Frederick Pennington, was the Headmaster of the Albert Schools in Marple when Donald was born.
[6][7] On the 23 1955 he spoke on a forty five minute radio broadcast programme with Veronica Wedgwood and Hugh Trevor-Roper, about the causes of the English Civil War.
[10] In 1956 Donald was actively engaged in the work of the National Committee for the Abolition of Nuclear Weapons Tests which was a precursor of the CND.
[10] He became a founding member of the Campaign for Nuclear Disarmament (CND) and was involved with that organisation from the outset.
[3] His works include Europe in the Seventeenth Century, Members of the Long Parliament (with D. Bruton) and Puritans and Revolutionaries, Essays Presented to Christopher Hill (with Keith Thomas).