Why did Timur rule through puppet khans of the Chagatai line?

Timur never formally assumed the full attributes of sovereignty, preferring to rule as an emir while maintaining the fictional authority of puppet khans from the Chagatai line. By upholding these figures, he provided a traditional legitimacy to his rule, as he claimed kinship with the Chagataid khans through marriage. This connection allowed him to style himself gūregen, meaning "son-in-law" of the khan.1

This arrangement allowed Timur to exercise absolute power while operating within the established political framework of the region, effectively positioning himself as the restorer of the Mongol empire without needing to claim the title of khan himself.21