The buyout will add 28 new hotels to the group’s portfolio from across the world.
Through the transaction, AccorHotels, which achieved a double-digit increase in revenue through acquisitions last year, has now taken a 50% stake in the company and has pledged to create a strategic partnership.
"Mantis is a pioneer in customized one-of-a-kind travel services in some of the most imaginative hotels across the world,” said Sebastien Bazin, Chairman and CEO, AccorHotels.
“With this strategic partnership, we are reinforcing the Group's footprint in Africa and we have access to a brand with strong roots and heritage, recognised for its commitment to preserve the environment and its prestigious credentials in the hospitality space."
Founder and Chairman of the Mantis Group, Adrian Gardiner, added: "AccorHotels is one of the fastest growing hotel and travel operators worldwide
"This agreement presents an attractive proposition for the Mantis Group to utilize AccorHotels' robust distribution channels and world-wide reach to further develop the hospitality concepts and sustainability projects we have worked so tirelessly to grow. We are excited to embark upon this new chapter alongside AccorHotels where we will act as ambassadors for the development of both our Groups' portfolios and offerings."
The French multinational hotel group currently operates more than 200 hotels in the Middle East and Africa.
AccorHotels said that it intends to open a further 100 properties in the next five years as it tries to capitalise on the continent’s growing travel market.
The firm has also shifted its focus towards the luxury hotel market segment, acquiring Raffles, Fairmont and Swissôtel, in 2016.