The education career of one of the most influential but controversial figures in the schools system came to an abrupt halt this week as Lord Adonis was moved to the Department of Transport.

A schools minister since May 2005, the now 45-year-old has actually wielded power over teachers for more than a decade, and considerably more than his parliamentary undersecretary of state title would suggest.

Lord Adonis, a former Financial Times journalist, first came on the scene in 1998 as Tony Blair’s education adviser in the 10 Downing Street policy unit. It was a post that led some to dub him “the real education secretary”. Less flattering titles from educationalists included “Andrew Bloody Adonis”.

He has been heavily involved in everything from Excellence in Cities and the Gifted and Talented Programme to Teach First and trust schools. But it is for the academies programme that he will be most remembered. He did more than anyone else to promote the policy, a point illustrated this week by the polarised reactions to his sudden departure from the Department for Children, Schools and Families.

Anti-academy campaigners welcomed the news. Academy sponsors, by contrast, are devastated by the removal of their champion.

Lucy Heller, managing director of Ark Schools, said: “The loss for most of us is that Andrew has been a very rare thing - a politician with a mission. He has had no concern for self advancement, and academies was just something he was passionate about.”

His career may yet benefit from his passion for this subject. The Conservatives have now made academies the centrepiece of their education policy and have suggested that he could be offered a place in a future David Cameron government.

If he accepted - which may be unlikely following his condemnation of the Tories’ “free schools” policy this week - it would mean he would have been an active politician for all three of the main political parties.

A former Liberal Democrat Oxford city councillor, Lord Adonis still commands considerable respect from the party. David Laws, the Lib Dem schools spokesman, this week described his move as a “disgrace”.

But Lord Adonis, the son of a Greek Cypriot postman from north London, was creating controversy for Labour long before the academies concept was born. Educated at a minor public school thanks to a local authority bursary, he always admired the independent schools sector and does not share the traditional Labour hard support for comprehensive schools.

Differences over selection was just one source of tension in the relationship the then Downing Street adviser had with David Blunkett, Mr Blair’s first education secretary.

Another area of skirmishing was Chris Woodhead, then chief schools inspector, who Mr Blunkett wanted to get rid of in 1998 but was kept on thanks to the intervention of then Mr Adonis.

“What is the bloody point of my being here?” Mr Blunkett is reported to have screamed at the time. “Who is the education secretary, me or Andrew Adonis?”

Mr Blunkett’s successor, Estelle Morris, has also spoken publicly of her frustration of having to deal with “the Andrew Adonises of this world” while being education secretary. “Sometimes they were just plain wrong,” she said. “It was my job, not their job. I was elected, they were not elected.”

The adviser’s huge influence led to the late Ted Wragg, renowned educationalist and TES columnist, lampooning him as Tony Zoffis, in honour of the response that he received whenever he asked where the Government’s latest “moronic” education idea had sprung from.

Moronic or not, in 2005 Andrew Adonis was ennobled and became the schools minister in charge of academies, a position which also allowed him to help broaden the Blair government’s commitment to state sector diversity through trust schools.

Despite predictions to the contrary he survived a change of Prime Minister and has publicly insisted that the decision to involve local authorities in academies only helped to attract more sponsors.

But many suspect he has been unhappy with the changes introduced by Ed Balls, the Schools Secretary. The TES also understands there has been resentment within the DCSF ministerial team, with suggestions that Lord Adonis has not been a “team player”.

This week the Conservatives claimed that Mr Balls had had his junior minister “kicked out”. However, Lord Adonis insists that he actually asked for a move in the summer, and those who know him say he is genuinely enthused about his new transport portfolio.

Whatever the truth, it is testament to the mark he has made on schools that so much public fuss is being made about the departure of such a, technically, junior minister.

Lord Adonis’s final place in history will depend on whether the academy programme he has done so much to promote is ultimately seen as a success. And on that point the jury is still out.