Río Biobío
In 1823, Chilean minister Mariano Egaña had a project approved by Congress to colonize the territory between Imperial River and Bío Bío River, establishing a series of forts on the northern shores of Imperial and Cautín Rivers in the middle of Araucanía. Chilean president Ramón Freire adopted the project initially but was later convinced to focus instead on the expulsion of the Spanish from Chiloé Archipelago, leaving the Araucanía issue pending.