From Halopedia, the Halo wiki
MEGA Brands is a children's toy company based in Montreal, Canada. It is the world's second biggest manufacturer of construction toys, the first being Lego, and one of the fastest-growing toy brands in the world. It owns the Mega Construx brand that uses several licensing rights for several franchises such as Halo and Destiny.
Halo Wars: The Authentic Collectors Series
In 2009 the first sets of Halo were released under the title "Halo Wars: The Authentic Collectors Series" which were sets based mostly on the game Halo Wars.
Halo: The Authentic Collectors Series
In around 2010 MEGA rebranded their sets into "Halo: The Authentic Collectors Series".
In around 2012 MEGA rebranded their Halo sets into "Halo".