Since prehistoric times sun worship continued in other forms and within many religions. In ancient nature worship the swastika represented the sun itself, planetary motion, the regular procession of the seasons, harmony of the forces of nature etc. There have been innumerable variations in the symbolism of the swastika. Not surprisingly, it crops up quite often as an element in the decorative styles of many early cultures.

For more information:
see Sunsigns and Swastika in An Illustrated Dictionary of Ornament by Ware & Stafford ISBN 0 04 729001 3 or in the Encyclopedia Britannicalook under Symbolism in Religion.