Complex sentence: He participated in the battles against the Swedes in 1626-9, then under the command of Hetman Stanislaw Koniecpolski took part in the suppression of the Taras Fiedorowicz Cossack uprising in 1630-1631.
Split into simpler sentences: He participated in the battles against the Swedes (1626-1629). Then under the command of Hetman Stanislaw Koniecpolski took part in the suppression of the Taras Fiedorowicz Cossack uprising in 1630-1631.