The actor Simon MacKenzie was best known for his leading role in the long-running Gaelic television soap, Machair, in which he played the dignified head of a further education college.

He had been a BBC broadcaster on the Gaelic radio news services and went on to become Scotland’s most prolific Gaelic arts activist, appearing almost constantly in films, videos, plays and live events for nearly 30 years.

As Scotland’s first Minister for Gaelic, Brian Wilson, put it: “Nobody did more for Gaelic over the last few decades than Simon MacKenzie.”

Simon MacKenzie was born in 1949 in Leverburgh, on Harris in the Outer Hebrides. His father was a farmer (his family owned 11 of the islands) but MacKenzie had resolved from an early age to be involved in the arts, an unusual career choice in the Outer Hebrides in the early 1950s.

After university at Aberdeen, where he read Celtic, he joined the BBC and worked closely with Wilson, whose newly launched newspaper, The West Highland Free Press, had a useful contract to provide the BBC with three news items a night in exchange for £25 a week. After leaving the BBC to train in Bristol as an actor, MacKenzie (or Sheem, as he was known to the Gaels) returned to the Gaelic heartlands just as significant funding was beginning to be made available to the rapidly declining culture.

He was everywhere — films, television, radio, theatre — and was soon seen as being one of the leading players on the Gaelic arts scene and reaching a wide audience in his role in Machair.

In addition to his talent as a performer, singer and writer, MacKenzie had a reputation for reliability; he took his work very seriously, being driven by a conviction that his culture was in peril — which it was and, indeed, still is.

He worked for many years in John McGrath’s 7:84 theatre company, with which he visited Russia, and spent nine years touring Highland schools with Gaelic plays, some of which he had written himself.

Latterly he became a director of the first national Gaelic theatre and was a senior lecturer at the £7 million Sal Mhor Gaelic College in Skye.

Politically adept, MacKenzie was able to move easily between the traditional, taciturn Gaels in their dark suits and even darker moods and the more upbeat and modern-leaning Gaels, many of them earning their living in the media.

Owning no kilt, he was usually attired in smart Harris tweed suits and took great pleasure in his immaculate flat in a lodge house near Helensburgh. He was an avid book collector, largely on Gaelic history.

He is survived by his long-term partner, Charlie Curran.

Simon MacKenzie, actor and activist for the Gaelic culture, was born on December 4, 1949. He died of cancer on April 8, 2008, aged 58