The township was organized April 6, 1858, by the election of J. O. Corey as supervisor; J. S. Cumming, clerk; T. F. Norton, assessor; A. S. Blakeslee, collector; Andrew Sprague, John Gower and R. C. Myer as commissioner of highways; Isaac Ames and A. J. Hopkins, constables.

[4] The early settlers of Sunbury Township found mostly rolling prairie with little timber.

Early settlement was primarily near Mud Creek in the southwest corner of the township.

[4] John V. Hilton settled in the area in 1842 making the journey overland from Buffalo, New York.

He traveled overland with horse and oxen, bringing his sheep, cattle and hogs with him.

He and his son Sylvester built a new home and the cabin was converted into a blacksmith shop.

John Blackmore and son Henry came here in 1849, having previously lived in Danville and Ottawa, Illinois.

Blakeslee took up a claim on the prairie in the central part of the township where there were no other settlers.

[8] Thomas F. Norton was a native of Maine and settled in the northeastern part of the township.

This opened the area to immigrants and also to the laborers who had worked on the railroad line construction.

[11] At the first election for county officers held November 6, 1858, there were 34 votes cast in the township.

The report of Thomas F. Norton, the first school treasurer, shows that “in 1855 there was but one school, thirty-four scholars in attendance, ninety-two children in the township, and but one teacher; the highest wages paid was $12 per month, and the whole amount paid out for school purposes was $38.75; there were but 107 school books in all the houses, sixty-five of which were elementary spellers.”[11] In the early years, the settlers received their mail at the little post office in Esmen Township which was on the mail route from Danville to Ottawa, Illinois.

The post office was called Sunbury and kept at the William K. Brown residence.

In 1870, when the town of Blackstone was established in Sunbury Township, the post office was moved there.

St. Bernard's Catholic Church was built in 1880 on the northeast quarter of section 10, one-half mile south of the village of Budd.