Buddhism and its spread in the Classical Age

There are thousands of little reasons that could attribute the reason that Buddhism spread in the Classical age, but mostly there were three powerful men who greatly enhanced Buddhism's geopolitical range.
The first man, Alexander the Great, took down the Persian empire and invaded the Punjab, raiding forts and settlements along the Indus River, and even forcing a major army of India's aristocracy to surrender at the battle of Hyspades, greatly pressured the current Indian dynasty in power, and led the way for the Mauryan dynasty to gain power. The Hellenism on the eastern border of India offered a path for many philosophers from India to take, where they diffused their ideas into different parts of Western society.
The second major player in the spread of Buddhism was Ashoka, the third king in the Mauryan dynasty, who after the battle of Kalinga converted to Buddhism, officialized it, and spread Gautama's ideas around the northern part of India. He also diffused the idea by having many merchants convert and disseminating into China.
The third and final effective diffuser of Buddhism was Wu Ti, who, though he was not a Buddhist, centralized the power in China enough, and established contact between the Uighur Turks so that Buddhism could be passively spread by merchants who would talk about ideas at business tables.