Couple of things:

First, the Republican party was formed specifically to abolish slavery.

Secondly, the United States was the first to codify the abolition of slavery into law.  In other nations prior to that, it either died out on its own or became some other form of servitude.

Third, the terrorism of which you speak was perpetrated mostly in the south by Democrat members of the Ku Klux Klan.

Lastly, while you make a fair point about Rosa Parks' contribution to the Civil Rights Movement, you totally ignore the contributions of activists such as Booker T. Washington and W.E.B. Du Bois, the principal founder of the NAACP.

I really have no idea of whether your party of choice supported 26 votes since 1933. The fact remains that it was ineffectual. Nothing changed for another 30 years.

Only because of vociferous opposition by Democrats in the corrdors of power in Washington and the southern states.  That is what made social activism by folks like Rosa Parks necessary, and the fact that Republicans championed such causes is precisely why they are my "party of choice".

Regards,
Scott Perry