Daniel D. Brockway was born in Morrisville, Vermont May 2, 1815, but many of the details of his early life are unclear. As a youth, be moved with his family to Franklin County, New York, and then Chicago, Illinois, before arriving in Washtenaw County in Lower Michigan in 1831. It seems likely that he moved to Kalamazoo County, Michigan, in the early 1830s as he was married to Lucena Harris in Kalamazoo County, Michigan on January 21, 1836. Lucena was the daughter of Dr. James Harris, a noted pioneer in the Galesburg area of Kalamazoo County. The Brockways spent several years (probably 1837-1839) back in Franklin County, New York, farming and smithing.

In August of 1843, Daniel, Lucena, and their daughters Charlotte and Delia moved to L'Anse, where Daniel had been appointed government blacksmith and mechanic at the federal Indian Center. Daniel’s brother, William, was serving as chaplain at Fort Brady in Sault Ste. Marie at the time and may have had an impact on the couple’s decision to assist the Indians in this remote region of Michigan. While in the Upper Peninsula, the Brockways had four more children; the first, Sarah, is reputed to be one of the first white children born in Lake Superior region.

Michigan's newly-discovered copper lands to the north of L'Anse were opened to mining in 1844 and by May 1846, the Brockways and their three children moved to Copper Harbor. They are reported to have built the town’s first house, which Daniel operated as a hotel for many years (he would later operate the Phoenix Hotel in Eagle River). Although the family moved back to Galesburg from 1869-1872, the Brockways developed a variety of businesses throughout the Upper Great Lakes region over the next five decades. Daniel became involved in the operations of various mining companies, both in Michigan and in other western mining regions. He was still agent for the Cliff Mine at the time of his retirement in the mid 1890s. He was involved in a great number of land ownership arrangements, individually and with other members of his family. These holdings included land in the Upper Michigan counties of Houghton, Keweenaw, and Marquette, and in the Lower Michigan counties of Kalamazoo and Washtenaw (where he had various business dealings with a brother in Flint, Michigan), as well as Tennessee, New York, and Ontario, Canada.

Daniel Brockway is perhaps best known for his mercantile activity. He operated an early store, Brockway and Perry, in Copper Harbor with his son-in-law G.W. Perry. This operation likely ceased when Daniel moved the family to Lower Michigan in 1869, but upon his return to the district in 1872, Brockway opened a new store, D.D. Brockway & Son, at the Cliff mine with son Albert. The store changed location several times over the next twenty-five years and serviced many of the mines in Keweenaw County. He held several patents and purchased rights for the resale of several other patented items. Brockway was also involved in various public offices and political activities, including service on the L'Anse Bay and State Line Road Commission, the Mineral State Road Commission, and the Kalamazoo County Road Commission; as delegate to the Republican state convention; and several stints as postmaster at Copper Harbor / Fort Wilkins. He also organized the first school in Copper Harbor, contracting Susan Warren to teach his children in the front room of the family house in 1849.

In 1895, at age 80, Daniel retired with wife Lucena to Lake Linden. Lucena died on March 3, 1899, with Daniel following two months later on May 9, 1899. They are buried in Lakeview Cemetery near Calumet, Michigan. The Brockways had six children: Charlotte L. Farwell, Delia H. Perry, Sarah ("Sallie") L. Scott, Albert, Anna M. Gray, and Daniel, Jr., who died young.