Kiltimagh, Co Mayo native Thomas Flatley emigrated to the US in 1950 with just over $30 to his name. Over the following 40 years or so, he established a $1.3bn property empire, initially focused on south Boston and the surrounding area, building offices, apartments, hotels, shopping centres, industrial parks and health centres.
At the height of its success, the company employed 5,800 people and owned property in 56 cities across seven states, and he also owned a New Hampshire TV station, according to one report.
The staunchly Catholic businessman died in 2008, and his family are giving away much of the fortune he built to good causes. At the end of 2015, it had 493m of assets, according to an official filing.