That party is one of the several ancestors of the Liberal party. The term has lost its original content and the adjective and now simply means Liberal.
BTW, in Canada the terms "liberal" and "Liberal" have different although sometimes overlapping meanings. The Upper case L signifies the federal party or the provincial parties.
The same distinction applies to "conservative" and "Conservative".
Yanks may be more familiat with another name for Liberals, to wit, Whigs. Whigs and Tories ought to be familiar from Revolutionary War history. Canadian Liberals are still sometimes called Whigs although less so than they are called Grits. Canadian Conservatives are still called Tories.
Now that we've gotten the Grits out of the way--at least to some extent--it's time to kiss and make up and carry on as though this terrible spat never happened. Do you suppose Quell Soap would cleanse both the U.S. and Canada of these parasites? DDT? Clorox?