General antonyms:
* Resist: To oppose or fight against something.
* Defy: To refuse to obey or submit to someone or something.
* Stand firm: To remain resolute and unwavering in the face of pressure.
* Persevere: To continue despite difficulties or obstacles.
Antonyms specific to surrender:
* Victory: To win or triumph.
* Conquer: To overcome or defeat someone or something.
* Prevail: To succeed or be victorious.
Antonyms specific to submission:
* Assert: To state firmly or confidently.
* Dominate: To rule or control someone or something.
* Independent: Not subject to the control of others.
The best antonym will depend on the specific situation and the meaning of "capitulate" in that context.