Spanish brought war dogs with them. These mastiffs and nice Danes were trained to kill, and that they were savage. all at once, sharp, sturdy steel, horses, and attack dogs additional to guns to present the Spanish a military edge that the Indians couldn't counter. Many of the men on the Cortés expedition of 1519 had ne'er seen combat before. The spanish’s biggest ally when fighting the aztec was smallpox.
No medieval force, notwithstanding however bloody-minded, may have achieved such huge levels of racial extermination. Instead, Europeans were power-assisted by a deadly secret weapon they weren't even aware they were carrying: pox.Smallpox may be a infection that sometimes enters the body through the nose or throat. From here the virus travels to the lungs, wherever it multiplies and spreads to the system a lymphatic um. at intervals many days, massive pustules begin to seem everywhere the victim's skin. beginning with the hands and also the face, and so spreading to hide the remainder of the body, every blister is packed jam-packed with pox polymer. If perforate, these blisters become extremely infectious, sticking recent pox particles into the air and onto close surfaces -such as somebody else's skin. it's a sickness that needs shut human contact to duplicate and survive.