Japan's biggest banks are breaking tradition by promoting foreigners to top management roles to retain and lure overseas talent as growth abroad buoys profit.

Among recent appointments: In July, Debra Hazelton became the first foreign general manager at Mizuho Financial Group Inc.'s headquarters, where she leads a new department to manage global staff.

Sumitomo Mitsui Financial Group Inc.'s lending arm promoted two foreigners to executive officer roles in April, and Mitsubishi UFJ Financial Group Inc.'s banking unit appointed its first non-Japanese executive officer last year.