Complex sentence: A Soviet proposal for enhanced autonomy for Nagorno-Karabakh within Azerbaijan satisfied neither side, and after the dissolution of the Soviet Union in 1991, a land war erupted between the Armenians and Azerbaijan over the disputed area.
Split into simpler sentences: A Soviet proposal for enhanced autonomy for Nagorno-Karabakh within Azerbaijan satisfied neither side. After the dissolution of the Soviet Union in 1991, a land war erupted between the Armenians and Azerbaijan over the disputed area.