They had allied with the French and then with the British during various phases of the colonial wars.

They had fought against the Americans in the Revolutionary War, regarding the new republic as the most threatening of the various colonial powers they had dealt with — more aggressive, more expansionist, more ideologically committed to the displacement of Native peoples than the colonial powers that had preceded it.

By the time Tecumseh was born, the Shawnee had been fighting Americans for most of a generation and losing.

Not in single battles — the Shawnee were capable fighters who won their share of engagements.