[3] In the 13th and 14th Centuries the Ministerialis (unfree knights in the service of a feudal overlord) family of Müllheim was mentioned.

The abbey and its successors (between 1540 and 1798 the Bishop of Constance) were the judicial rulers and landlords of the village.

The municipality had the right to impose fines and light corporal punishment The village church was probably first built, as part of Pfyn parish, around 1340.

It belonged to the Langenhart [de] parish (now a hamlet within northeast Müllheim) until 1483 and then to Hüttlingen.

In the course of the 20th Century, the portion of the inhabitants who follow the Swiss Reformed Church has increased.

The economy of Müllheim was characterized by wine, fruit, flax and hemp production as well as forestry and dairy farming and cheese making.

Other businesses in the municipality included an embroidery factory in 1900, a wood turning plant that was open between 1909–16 and a machine shop from 1906 to 1909.

Since 1954, a local company manufactures steel furniture, another has recycled industrial waste since 1991.

[4] The municipality is located in Frauenfeld District, on the southern edge of the Seerücken hills.

[6] The age distribution, as of 2009[update], in Müllheim is; 285 children or 10.8% of the population are between 0 and 9 years old and 387 teenagers or 14.7% are between 10 and 19.

[13] The historical population is given in the following table:[3][14] The region of Grüneck is designated as part of the Inventory of Swiss Heritage Sites.

[7] From the 2000 census[update], 709 or 29.6% were Roman Catholic, while 1,134 or 47.3% belonged to the Swiss Reformed Church.

Of the children in kindergarten, 26 or 47.3% are female, 9 or 16.4% are not Swiss citizens and 8 or 14.5% do not speak German natively.

The lower and upper primary levels begin at about age 5-6 and lasts for 6 years.

At the lower primary level, there are 43 children or 42.6% of the total population who are female, 16 or 15.8% are not Swiss citizens and 15 or 14.9% do not speak German natively.

In the upper primary level, there are 56 or 56.0% who are female, 9 or 9.0% are not Swiss citizens and 10 or 10.0% do not speak German natively.

There are 111 teenagers who are in the advanced school, of which 62 or 55.9% are female, 11 or 9.9% are not Swiss citizens and 7 or 6.3% do not speak German natively.

There are 74 teenagers who are in the standard school, of which 31 or 41.9% are female, 10 or 13.5% are not Swiss citizens and 10 or 13.5% do not speak German natively.

Finally, there are 9 teenagers who are in special or remedial classes, of which 7 or 77.8% are female, 3 or 33.3% are not Swiss citizens and 3 or 33.3% do not speak German natively.