MIDLINE, TEXAS. Midline is on the Southern Pacific line and U.S. Highway 59 two miles northeast of Splendora in extreme eastern Montgomery County. The area was in the John Cole survey and was first settled in the late 1830s. The town sprang up on the narrow-gauge Houston-Cleveland spur of the Houston, East and West Texas Railway; the spur was extended northeast from Splendora through Montgomery County about 1880. Around 1900 a lumber boom in the Piney Woods brought a number of settlers to the region. The community became a station on the Houston, East and West Texas, and by 1902 a post office had been established there and called Midline, for its location near the Montgomery-Liberty county line. The post office was discontinued about 1930. In the early 1930s State Highway 35 was extended through the town. By 1936 the community had only a few scattered farm dwellings and a single business. U.S. Highway 59 was built through Midline about 1940, and by 1941 the community had ten residences and three businesses. During the 1950s the Friendship Church was constructed a half mile southwest of the township. There were as many as a dozen residences in the community during the mid-1970s. In 1990 the Friendship Church still stood.
Montgomery County Genealogical Society, Montgomery County History (Winston-Salem, North Carolina: Hunter, 1981).