We had political parties long before we had primaries. Presidential primaries were only introduced in the 1970s. Primaries for state office were introduced in the 1890s, died out, and were introduced again in the 1920s.

But we had parties going basically back to the beginning of the country, and the current two parties crystallized during the 1850s -- long before primaries. Primaries were introduced as a way of reducing the power of party bosses over the parties.