Rubuta ci gaba don wannan sakin layi - Hagnon ya jagoranci rundunar soja don Athens a lokuta da dama, yana cikin jagorancin sojojin da suka tashi a kan Samos a cikin yakin Samian
na 440 BC kuma yana jagorantar rundunar da ta yi ƙoƙarin kama Potidaea a cikin 430 BC. A cikin 421 BC, yana ɗaya daga cikin 'yan Athens da suka sanya hannu kan Zaman Lafiya na Nicias, yarjejeniyar, wanda wani janar na Athens ya yi shawarwari tare da suna iri ɗaya da mahaifinsa (babu dangi), wanda ya kawo ƙarshen abin da ake kira Archidamian War, mataki na farko na Yaƙin Peloponnesian; ya kuma sanya hannu kan kawancen tsakanin Athens da Sparta wanda aka kammala a wannan shekarar.