- Henry Tudor had been in exile in Brittany since 1471 with Jasper.
- Richard III was on the throne and had never seen Tudor as a threat due to his week claim to the throne.
- Henry began to gain more support from rebellions against Richard III
- He gained support from France.
- King Charles VIII of France wanted to annex Burgundy.
- Richard made deal with Duke Francis II to supply duchy with company of english archers to defend from french invasion.
- Charles angry at interference so backed Henry and Lancastrian exiles.
- Offered financial and military assistance to supply invasion of England to prevent Richard helping Brittany.
- This was his opportunity.
- He set sail on French ships…