Nicola D’Ascenzo (1871 - 1954) was the most successful stained-glass artist in Philadelphia. His studio set national standards of excellence with windows, murals, and mosaics. By the 1950s his work was in 41 states and five countries.
D’Ascenzo arrived in the U. S. at age 11 from Torricella, Italy, where his family had been armor makers. He studied art at Philadelphia’s Academy of Fine Arts, as well as in New York and in Rome.

 D’Ascenzo’s Three Windows at First Reformed Church
1913 to 1922:

In 1905 Fred Lamb had created First Reformed Church’s Tiffany-esque chancel window of Jesus at Galilee. Nicola D’Ascenzo designed these next three windows, above. His windows repeat the sanctuary’s Classic Revival vibe with the use of stained-glass swags and other classical motifs.
Later, Joseph G. Reynolds brought his enthusiasm for Gothic Revival craftsmanship into the building, with his nine windows in a Medieval style.

The Archive of Nicola D’Ascenzo’s Studio
at the Athenaeum in Philadelphia: 

Photos of Nicola D’Ascenzo’s Studio
From the Archive at the Athenaeum:

 Nicola D’Ascezo: Honorary Member of
The American Institute of Architects:

  Above: Nicola D’Ascenzo associated with some of the leading American architects of his era. As a member of the American Institute of Architects he socialized with architects who designed the buildings that housed some of his most important windows. Those prominent architects included Paul Philippe Cret (Folger Shakespeare Library) and Milton Bennett Medary (Washington Memorial Chapel).
The journal Fortune Oct. 1930: “Professionally, perhaps, his [Nicola D’Ascenzo’s] greatest distinction is his honorary membership in the American Institue of Architects, the highest architectural body in the country, whose roster includes the pick of the profession. His election was a tribute to his contributions to American art through stained glass.”
“This honor has been conferred on only one other glass craftsman - Mr. [Charles] Connick. Mr. D’Ascenzo is, however, the only glassman who has won the Native Industrial Art Medal of the Architectural League of New York…”

 1916: Nicola D’Ascenzo Created 32 Windows
for the Reformed Church’s Seminary in Lancaster:

  Nicola D’Ascenzo was a favorite stained-glass designer for Lancaster’s German Reformed community. In 1913 and 1922 he installed First Church’s three stained glass windows. During that time he also created 32 medallion windows for the Reformed Seminary, located near F&M College. The college had also been established by Pennsylvania’s Reformed Church.
These 32 windows are in the seminary’s Dietz Refectory / Dining Room, built in 1916. Some of the glass was repurposed from historic greenhouses in Belgium that were damaged in World War I. This magnificent Tudor-Revival hall also includes Mercer tiles from Henry Mercer’s tile works in Doylestown.
D’Ascenzo later created windows for another Reformed school in nearby Franklin County: Mercersburg Academy. His clerestory windows in the academy’s chapel rise above aisle windows created by the Reformed Church’s other favorite stained-glass craftsman, Joseph G. Reynolds.

Elsewhere: 1932: Nicola D’Ascenzo’s Windows
in the Folger Shakespeare Library, Washington D.C.:

Elsewhere: Nicola D’Ascenzo’s Windows
In The Washington Chapel at Valley Forge: 

  Above: One of D’Ascenzo most celebrated achievements is his cycle of stained-glass windows in the Washington Memorial Chapel at Valley Forge. The towering Neo-Gothic windows have prompted some writers to describe this chapel as an American Sainte-Chapelle. D’Ascenzo created all the stained-glass in the chapel, in 13 windows. He completed the final window ca. 1920 after many years of work.

 Nicola D’Ascenzo ca. 1940:

Nicola D’Ascenzo and wife Myrtle (Goodwin) D’Ascenzo lived at Germantown, near Philadelphia. They were members of the Germantown Unitarian Church. They and their son, Nicola Jr., are buried at the Washington Chapel in Valley Forge.
D’Ascenzo chose his final resting place to be next-door to the chapel whose stained-glass windows represent his lifetime of artistic achievement. Image source: Artists…Rockport Art Association, 1940.