Mick Lally: Co-founder of the Druid Theatre Company and actor best known for playing farmers in 'Ballykissangel' and 'Glenroe'

To television viewers in Ireland, Mick Lally was forever associated with the role of Miley Byrne, an archetypal Irish farmer, in the Sunday-evening, soapy drama Glenroe. Lally's gormless character had previously appeared in the Irish series Bracken, starring Gabriel Byrne.

The actor developed a comedy double act with Joe Lynch, who played Miley's cantankerous father, the lovable rogue Dinny, in both Bracken (1978-82) and Glenroe (1983-2001), the spin-off that saw the pair sell their farm to move over the mountain, closer to Dublin but still in Co Wicklow.

Much of the action in Glenroe's early years revolved around Miley's courtship with Biddy McDermott and their subsequent marriage. Other stories came from the couple's extended families. Following Biddy's death in a road accident, the final series centred on Miley's coming to terms with his loss and the struggles to raise their two daughters.

The crumpled face and croaky voice then became familiar to British viewers when Lally took on the role of another farmer, Louis Dargan, in another Sunday-evening drama, Ballykissangel. Seen during the final run of the BBC series, in 2001, the unmarried Louis lived close to the breadline in the fictional village that was based on the creator Kieran Prendiville's memories of childhood holidays in Co Kerry, although Ballykissangel was actually filmed in Co Wicklow.

Nevertheless, the farmer, who survived on EU grants, managed to become part of the fixtures and fittings at Fitzgerald's bar and, although dubious about the Roman Catholic faith, attended church as an insurance policy – just in case!

Instead of making his Irish accent more coherent for a British audience, the actor was under instructions to do the opposite. "He's quite a gruff individual – most of the time when he speaks, nobody knows what he's saying," explained Lally of the character. "He has an incomprehensible accent, a kind of verbal communication only he understands. I remember the first few days on set, the director continually telling me, 'No, no, Mick, the accent is still too clear'. The role of Louis goes against one of the most basic things you learn as an actor – clarity and making sure the audience understands you. Rather than being understood, it seems that Louis exists to be misunderstood!"

Born in Tourmakeady, Co Mayo, in 1945, Lally was the eldest child in a family of two boys and five girls. After attending St Mary's College, Galway, he graduated in Irish and history from University College, Galway – where he acted and showed a talent for boxing – and became a schoolteacher in the Co Galway market town of Tuam from 1969 to 1975.

He continued to act with the university's drama society and then, in 1970, joined the Irish-language theatre company An Taibhdhearc, in Galway, appearing in up to eight productions a year. Unable to support himself without a day job, Lally turned down a place with the Abbey School of Acting, at Dublin's Abbey Theatre.

Then, in 1975, with his fellow St Mary's College graduates Garry Hynes and Marie Mullen, he founded the Druid Theatre Company. From its Galway roots it became a major institution in Irish theatre, partly thanks to the success of plays such as JM Synge's tragic-comic The Playboy of the Western World, its inaugural production, in which Lally acted Old Mahon, the survivor of two murder attempts by his son, Christy, who boasts about killing his father.

Lally later starred as the lame Manus, who becomes involved in a love triangle in the premiere of Brian Friel's play Translations (Guildhall, Derry, 1980), staged by the Field Day Theatre Company.

By then, he had made his first screen appearances, in Bracken – winning a 1979 Jacob's Award for his performance as Miley – and Poitín (1978), the first entirely Gaelic-language feature film. (A fluent Irish speaker, Lally constantly returned to plays and screen productions in his native language.)

His other films included the director Neil Jordan's first feature, Angel (1982), the Irish War of Independence drama Fools of Fortune (1990), Circle of Friends (1995) and the epic Alexander (2004), directed by Oliver Stone.

On the small screen, he flitted between Irish- and British-made programmes, from Strumpet City (1980), produced by the Irish television network RTE, to the BBC television film The Ballroom of Romance (1982) and The Irish RM (1983), a co-production between Channel Four, RTE and Ulster Television.

Lally was also seen as a horse trainer in the international co-production Scarlett (1994), a mini-series adaptation of Alexandra Ripley's Gone with the Wind sequel. Later, he joined the Irish-language soap opera Ros na Rú*as the mysterious, self-made millionaire Eamonn De Faoite (2008-09).

But it was the role of Miley Byrne that followed Lally throughout his career – and brought him success outside acting. In 1990, he had a No 1 hit single in Ireland with his performance of "The By-Road to Glenroe", a song from the programme.

During his long run in the drama, Lally once played an April Fools' joke on the radio programme Morning Ireland, announcing that he was leaving Glenroe because RTE was insisting on introducing nude scenes.

The actor is survived by his wife, Peggy, and their three children.

Michael Lally, actor: born Tourmakeady, Co Mayo, Ireland November 1945; married Peggy (two sons, one daughter); died 31 August 2010.