The life of my father, John McNair, who has died aged 93, was shaped by a sense of moral purpose and social commitment, rooted in his Presbyterian upbringing in Liverpool. Graduating in modern languages from Cambridge in 1940, he was a conscientious objector but quickly came to see the second world war as legitimate. He served in North Africa and Germany, was awarded the Military Cross, and on leave in 1942 married Rene Brookes, whom he had met through the Holiday Fellowship, and with whom he shared a love of walking, music, literature and theatre.
After the war he began his lengthy commitment to the Labour party, campaigning in every national and local election for 60 years. He joined Haberdashers' Aske's school, which was then in Cricklewood, north-west London, but later relocated to Elstree, Hertfordshire, where he became head of languages and the sixth form. He championed the Spanish language and introduced the use of tape recorders and television into language teaching.
In 1966 he moved to the education department of Manchester University, where he trained a generation of language teachers. As retirement approached, he undertook a study of the Spanish education system, touring Spain in a caravan with Rene, visiting schools and colleges and producing the book Education for a Changing Spain (1984), which was for some years the authoritative text on the subject.
They retired to Todmorden, in West Yorkshire, to be near the hills and still close to the university library. Losing his bladder to cancer at 65, he became regional secretary of the Urostomy Association, providing support to many fellow sufferers. He was a school governor, a reader for the talking books service for blind people and a volunteer for Citizens Advice and the hospital car service. He helped found Todmorden Easy Theatregoing, which still takes coachloads of people to the theatre every month. At the age of 87 he founded the Todmorden branch of the University of the Third Age.
He was a devoted husband, nursing Rene through her final illness five years ago, and continued to live independently at home to the end despite his severely declining health. He never sought the limelight but he changed the lives of hundreds of people as a teacher, activist, neighbour and friend. A lifelong socialist and Guardian reader, he was determined to make the world a better and fairer place.
He is survived by my sister Barbara and myself, four grandchildren and two great-grandchildren.