Having been written off as a spent force, they were back yesterday with more than 10 per cent of the vote and 59 seats in the Chamber of Deputies - twice as many as they had dreamed of capturing.
The man with the power to make or break Romano Prodi's incipient centre- left government is the League's quixotic leader, Umberto "Braveheart" Bossi, 54, who thrives on his unkempt appearance and thuggish manner. He has been the thorn in the establishment's side for years, playing a big role toppling the old governing parties in the early 1990s and, two years ago, joining and toppling the conservative coalition government headed by Silvio Berlusconi.
Quite what he stands for is not clear. Ostensibly, he wants to split the affluent north from the rest of the country and set up an independent republic. But Mr Bossi is too intelligent to take full separatism entirely seriously. Certainly he wants to diminish the corrupt and inefficient influence of Rome.
His real interest though is to shake up the establishment and make sure it does not settle into its lazy old ways. He is a one-man vanguard of the revolution, and a consummate political strategist. As such, he has attracted a massive protest vote, especially in the north, where disillusion with Mr Berlusconi runs high and the centre-left is viewed with suspicion. "We won't be in parliament just as benevolent onlookers," Mr Bossi said yesterday. "We in the League are fighters."