Introducing Biffo, Ireland's Taoiseach waiting in the wings

Bertie Ahern's sudden resignation clears the path for Brian Cowen. But who is the man behind the acronym?

Bertie Ahern (left) and Brian Cowen, as Ahern announced his resignation as Taoiseach last Wednesday (PA)

Brian Cowen, who will succeed Bertie Ahern as Prime Minister of the Irish Republic, looks like providing the government with continuity of policy but with a very different personal style.

His experience and ability means that there are no other serious contenders for the job abruptly vacated by Mr Ahern, who had become enmeshed in financial scandals. But although the present Taoiseach is known as a consummate conciliator, his successor has a reputation for combativeness. In his younger days this enthusiastic heckler in the Dail (Irish parliament) was known as "gurrier-in-chief".

While Mr Ahern was the most popular nationalist politician of his generation, Mr Cowen commands formidable respect within the Dail. He has been there for almost a quarter of a century, evolving during that time from belligerent backbencher to a respected heavyweight who has held six important cabinet posts.

While he rates high in the opinion polls, Mr Cowen has yet to make the same phenomenal connection with the public as did Mr Ahern, whose standing until recent times far outstripped that of his Fianna Fail party. But like Mr Ahern he is regarded as "Fianna Fail to the backbone", coming from a staunch party family. He entered the Dail at the age of 24, taking the seat of his father, who had died suddenly.

Married with two children, he was a solicitor before his father's death propelled him into politics. He is firmly grounded in the not particularly fashionable county of Offaly, where his family has had a pub for generations. One minor embarrassment came recently with the news that his publican brother was a tax defaulter who had been ordered to pay almost €100,000 (£78,000) in taxes and fines. Mr Cowen explained that he had "no involvement whatsoever in my brother's business".

He himself has a reputation for enjoying sessions in pubs, and taking part in sing-songs, one of which was recorded for charity. Last year he admitted that he had tried a joint in his student days, quipping that unlike Bill Clinton he had actually inhaled. He is talented at both mimicry and joke-telling, which provide a useful counterpoint to his reputation as one of the Dail's smartest men.

Over the years Mr Cowen firmly squashed any suggestion that he might urge Mr Ahern to stand down in his favour. He stuck with Mr Ahern even during the past few weeks, when it was evident the leader was in serious trouble. Even when the opposition put him under pressure to make anti-Ahern, moves he brushed them aside.

During a Dail debate in February, he adamantly refused to distance himself from Mr Ahern while at the same time enhancing his own standing by almost contemptuously swatting opposition leader Enda Kenny aside with a bravura performance. But the question remains whether he can combine his natural combativeness with more diplomatic qualities. These are particularly important in Dublin since the Fianna Fail party, although the largest in the Republic, always requires political partners to hold office.

Mr Ahern proved himself a master of the delicate wheeling and dealing involved in building and maintaining coalitions. While the present administration is expected to continue, with a smooth hand-over at the top, the future will certainly provide vital tests of Mr Cowen's ability to bring together disparate elements. He will also be expected to repeat Mr Ahern's success in establishing working relationships with Northern Unionists and ensuring that North-South relations continue to run smoothly.

Like others from his home county, he has had to absorb the long-standing insult of Biffo, taken to mean "Big ignorant fecker from Offaly". Mr Cowen is sometimes referred to as Biffo, though he and other Offalians profess to believe it really signifies "Beautiful intelligent fellow from Offaly".