Of those, 6.4 million moved after large-scale flooding, droughts and other natural disasters, while 1.2 million were forced out by large-scale construction projects like dams.
But once researchers began gathering information from local and national government, private companies, development banks, the World Bank and activist groups they soon abandon an initial estimate of 1.7 million people.
Data on people forced to migrate by disasters came from government departments.
Many more have probably been forced to move by Brazil’s soaring violent crime rates, but a “code of silence” makes compiling that data impossible, Muggah said.
The interactive FMO platform presents data, maps and video and includes emblematic cases of mega-projects and natural disasters such as the 2015 Mariana dam collapse in which 19 people died and nearly 1,400 lost their homes.
Floods in the north-east of Brazil in 2009 killed 43 people and forced 343,000 from their homes.
In 2015 alone, 64,000 people moved because of a five-year drought in the semi-arid interior regions of Brazil’s north-east.
In 2000 10,000 people were moved for the Itá dam in the south of the country, the FMO calculated.
Activist groups said numbers could be much higher and that migrants suffered from a lack of decent housing and government care.
“There is a lack of water.