His friend Samuel Jarvis had helped found the General Theological Seminary in New York and knew about the Cambridge Camden Society.

[3] This congregation was admitted to the Episcopal Diocese of Pennsylvania on 22 May 1846 and on 26 September 1846, took the corporate name of "Rector, Church Wardens and Vestrymen of St. James the Less."

The new congregation acquired land from nearby Laurel Hill Cemetery and wanted to build a church that could serve not only the wealthy families with mansions overlooking the Schuylkill River or on Hunting Park Avenue, but also working-class people of the nearby industrial neighborhood now known as Allegheny West.

Further modernization occurred in the early 20th century, including not only the tower and chimes (dedicated 1910) but also electric lighting and central heat circa 1913.

The congregation applied to the Cambridge Camden Society, which in 1841 and 1844 had published a widely circulated pamphlet on modern church design, for a set of approved plans.

[9] In 2001, the diocese initiated litigation to seize its property and two years later the Philadelphia County Court of Common Pleas ruled that the attempted merger was ultra vires and invalid.

The breakaway congregation largely entered the Roman Catholic Church under the provision of the Personal Ordinariate of the Chair of St. Peter established by Pope Benedict.

As part of its mandate, Saint Mark's Church began a fundraising effort to open a new parish school to serve this local community.