Complex sentence: Hunza was an independent principality for more than 900 years, until the British gained control of it and the neighbouring valley of Nagar between 1889 and 1892 through a military conquest.
Split into simpler sentences: Hunza was an independent principality for more than 900 years. The British gained control of Hunza and the neighbouring valley of Nagar between 1889 and 1892 through a military conquest.