David Swann, leader of the Liberals
While federal parties do not hold power at the provincial level, the federal party with the most elected members in Alberta is the Conservative Party.
Since the 2012 election, Danielle Smith, leader of the Wildrose Party has been Leader of the Opposition in Alberta.
Progressive Conservative Party of Canada.
He is leader of the UK Conservative party.
He was the leader of the Liberal-Conservative Party.
The Conservatives, or rather, the Progressive Conservative party.
Steven Haper was never leader of the conservative party. It's current leader is Stephen Joseph Harper, and he became leader of the conservative party on January 12, 2004
Margaret Thatcher became Leader of the Conservative Party on the 11th February 1975.
He has always been the leader of the Conservative Party of Canada, since its creation in 2003 to present.
The (British) Conservative Party
The premier becomes the premier when the provincial party (in this case, being the Alberta PC party) gets the most votes. The leader of that party then becomes Premier of Alberta. The citizens of Alberta choose the Premier by voting for MLAs of specific parties. The more votes for MLAs of a particular party, the higher the chance that the leader of that political party of Alberta will become Premier.
Conservative.