Why did Anne of Brittany become queen of France instead of Maximilian I’s wife?

Anne of Brittany became queen of France because King Charles VIII of France invaded her duchy to prevent it from falling under the control of a foreign power. Although Anne had married Maximilian I by proxy in 1490, the French military pressure forced her to break that union.12

Charles VIII, who had previously been betrothed to Maximilian’s daughter, Margaret of Austria, sent Margaret back to her father and compelled Anne to marry him instead on December 6, 1491. This marriage effectively initiated the union of Brittany with the French crown.123