It says it’s made by the Colonial Piano Company, of Boston, MA. This company is no longer in business, but they are listed in a 1911 directory of Boston Directors:
The Directory of Directors in the City of Boston and Vicinity
Their president, Mr. Bonney, is listed in the 1904 edition of Clark’s Boston Blue Book:
Clark’s Boston Blue Book
But I can’t seem to find a comprehensive history of the company. Either way, it suggests that our piano was made around the beginning of the 20th century. Neat! Now all we have to do is get it in tune.