TORONTO — He arrived in Toronto, an exhausted 16-year-old, carrying nothing but a small gym bag packed with a change of clothes. As a Somali, he applied for asylum and was jettisoned into adulthood. He registered for high school, learned to cook and landed his first job all on his own.

Over the next 25 years, he put himself through college and law school, worked his way up from pouring coffee to advising one of the country’s most powerful leaders and was elected the first Somali-Canadian member of Parliament.

Last January, he set another milestone for refugees to Canada: Ahmed Hussen was named the country’s immigration czar, the first refugee in that powerful cabinet position.

Yet Mr. Hussen has rarely talked about this journey. His closest friends and colleagues, all of whom describe him as a gifted conversationalist, say Mr. Hussen never confided the intimate details of his harrowing story.