Complex sentence: Tulips were an essential part of the gardens of Persia, having been cultivated from the Steppes, and as the Seljuks moved west they took tulips with them to Turkey, where many escaped cultivation and became naturalised.
Split into simpler sentences: Tulips were an essential part of the gardens of Persia, having been cultivated from the Steppes. Oghuz-Turkic leaders originated from the steppes--moved to Persia, and then west, they took tulips with them to Turkey, where many escaped cultivation and became naturalised.