Analysis of information sources in references of the Wikipedia article "Székelys" in English language version.
...the Szekler community, now regarded as a subgroup of the Hungarian people.
Székely, a Hungarian sub-group that is concentrated in the mountainous Hungarian enclave.
CIs. for the admixture time(s) overlap but predate the Mongol empire, with estimates from 440 to 1080 CE. In each population, one source group has at least some ancestry related to Northeast Asians, with ~2 to 4% of these groups total ancestry linking directly to East Asia. This signal might correspond to a small genetic legacy from invasions of peoples from the Asian steppes (e.g., the Huns, Avesta, Magyars, and Bulgars) during the first millennium CE.
Hungari et Siculi eadem lingua utuntur, nisi quod Siculi quaendam peculiaria gentis suae habeant vocabula