The land that today is Grunthal was the territory of several Indigenous groups through the recent centuries. The Cree, Anishinaabe and Sioux occupied the land initially.
As fur traders came through, the Metis began to live on the land and take part in the massive bison hunts that were a fixture of much of the 19th century.
Today, Grunthal sits on Treaty 1 land.
Eventually, settlers, mostly Russian Mennonites, came to the area in 1876. Six families established the Village of Gruenthal, nearby to the current community as part of this first wave of immigration. They would form the base of the community and as more immigrants arrived, the community started to grow.
At first, there was no official school house in the area and classes were held in homes with the father of the household serving as the tutor. Boys were taught from age six to 14, while girls were taught from age six to 12.
The first person to officially hold the title of teacher was Klaas Peters, who taught students in 1884, followed by Johann Klassen, who taught afterwards.
The first school in the area was built in 1888 as part of a machine shed and Jacob Wiebe was the first teacher. The second school was built in 1898, and would later be moved into town to become a home.
Dr. Peters arrived in the early 1890s and began a medical practice for the people of the new community. Not only was he the local doctor, but he also had the only store for many kilometres until a store was built by Johann Braun and John Krahn in 1892.
That same year, a feed mill was constructed and a steam engine was brought in to saw logs at the local sawmill. This saw mill was capable of sawing 4,000 feet of lumber per day.
By the summer of 1901, various Ukrainian settlers started to arrive and settled in the district. At the same time, many Polish immigrants arrived as well, giving Grunthal a unique multicultural aspect.
On July 14, 1970, the community received a very high profile visitor when Queen Elizabeth II and her family arrived to celebrate the 100th anniversary of the founding of Grunthal.
For the visit, the Queen, Princess Anne and Prince Charles all visited. The Queen had attended ceremonies in Steinbach and then drove through Grunthal on her way to St. Pierre. On the streets of the community, everyone was out and cheering for her. It was believed nearly every person from miles around, at least 2000 people, far more than who lived in the hamlet, were on hand to see her go by.
After she had driven through the community, hundreds of people stayed behind and took part in the chicken barbecue on Main Street.