Davis, who has worked at Vanguard for the past 13 years, will be responsible for leading Vanguard Australia and managing a range of equity and fixed income portfolios for both Australian and Asian investors.
Davis joined Vanguard in 1999 from Merrill Lynch and previously held positions as principal and head of bond indexing in Vanguard's Fixed Income Group.
He will be based at Vanguard's Australian head office in Melbourne for his new appointment as chief investment officer.
Davis takes over the position from Joe Brennan, who remains with the company, moving to a senior role with the investment team at Vanguard's Pennsylvania headquarters.