Complex sentence: "unincorporated" was coined to legitimize the U.S. late 19th century territorial acquisition without citizenship and their administration without constitutional protections temporarily until Congress made other provisions, and to impose discriminatory tax regimes with the effect of a protective tariff upon territorial regions but not domestic states.
Split into simpler sentences: unincorporated was coined to legitimize the U.S. late 19th century territorial acquisition without citizenship and their administration without constitutional protections temporarily until Congress made other provisions. The case law allowed Congress to impose discriminatory tax regimes with the effect of a protective tariff upon territorial regions which were not domestic states.