If you regard the political continuum (right to left) as a belief in the degree of government control over the individual, the "extreme right" consists of anarchists who believe in absolutely no government/law restricting the individual. Yet, when anarchy looms the resulting chaos frequently sets the conditions for an individual strongman or junta on the far left, who promises to, and may actually restore order, with no constraints whatsoever on his/their power.
So while the two may not exactly meet per se, one frequently presupposes the other. Often times, quite deliberately so.
The only reason Hitler came to power was as a delayed reaction to the fact that the Communists had seized power in Munich, Hungary, and Russia and had tried seizing power in Berlin and many other places in the aftermath of World War I. The votes for Hitler (in the runup to 1933) were to a great extent from women who feared the Communist threat and sought security, never dreaming what AH was really like.