Ignacy Żagiell was born on 14 February 1826 in either the manor of Pavirinčiai or Kelpšiškiai, then part of the Russian Empire.

After briefly working as a physician in Odessa, Żagiell traveled to Western Europe, where he continued learning about medicine in Paris, Berlin, Dresden, Prague, and Vienna.

From 1859, Żagiell worked as an army physician in Great Britain, briefly studying at Oxford and Paris.

A famous occultist, Żagiell was made an honorary member of Oxford University.

He lived in Vilnius and became the city's sanitary commission's president.