Why did Bernardo O’Higgins and the Carrera brothers flee to Argentina after the Battle of Rancagua?

Following the Battle of Rancagua on October 1–2, 1814, Spanish royalist forces reestablished their military supremacy in Chile, effectively ending the period known as la patria vieja ("the old fatherland").12

Faced with this defeat and the restoration of Spanish control, patriot leaders—including Bernardo O’Higgins and the Carrera brothers—were forced to flee across the Andes to Argentina.12

This migration served as a strategic turning point for the independence movement. While in Argentina, O’Higgins secured the support of José de San Martín, who was organizing an army to liberate the region. This collaboration eventually led to the successful campaign across the Andes and the decisive patriot victory at the Battle of Chacabuco in 1817, which paved the way for Chilean independence.312