Complex sentence: Themistocles took the money but reneged on the agreement and, even though bonds of hospitality between them required good faith, he accepted a bribe from someone else in a new deal that excluded Timocreon.
Split into simpler sentences: Themistocles took the money but reneged on the deal, even though bonds of hospitality required good faith. He had accepted a bribe from someone else in a new deal that excluded Timocreon.