Complex sentence: During the colonial period many Spanish, Crypto Jews had Intermarried with the Caxcans making many Caxcan Decedents Mestizo, and allied tribes settled the Caxcan lands in Zacatecas and Jalisco.
Split into simpler sentences: During the colonial period many Spanish, some of them Crypto-Jews, had intermarried, or had relations, with the Caxcans making many Caxcan descendants mestizos. They and allied tribes settled the Caxcan lands in Zacatecas and Jalisco.