This answer brought upon them the forces of the Mexican monarch, and a pitched battle was fought in which the republic was again victorious, but from that time hostilities never ceased between the two nations, every captive was mercilessly sacrificed, and the Tlascalan children were trained from the cradle to hate the Mexicans with a deadly hatred. In this struggle the Tlascalans received valuable support from a wild and warlike race from the north, called the Otomies. Some of them settled in the republic, and having proved themselves courageous and faithful, were entrusted with the defence of the frontier. After Montezuma became emperor of Mexico greater efforts than before were made to subdue Tlascala. He sent a great army against it, commanded by his favourite son, but his troops were defeated and his son killed. Enraged and mortified, Montezuma made still greater preparations and invaded the valley with a terrific force. But the Tlascalans withdrew to the recesses of the hills, and watching their opportunity, swept down upon the enemy and drove them from their territory with dreadful slaughter. Nevertheless they were greatly harassed by these constant struggles with a foe so superior to themselves in numbers and resources. The Aztec armies lay between them and the coast, cutting off all possibility of obtaining any supplies. There were some things, as cotton, cacas, and salt, which they were unable to grow or manufacture, of which they had been deprived for more than fifty years, and their taste was so much affected by this enforced abstinence that they did not get used to eating salt with their food for several generations after the conquest. This was the state of affairs in Tlascala when the Spaniards reached it, and it is easy to see how important it was to Cortes to form an alliance with it, but that was not an easy thing to do.