Delaware's Christmas landscape is a rich blend of diverse traditions, with Orthodox Christian groups—Greek, Ukrainian, and Russian—contributing a distinct layer. Early 20th century immigrants established these communities and have maintained their unique religious and cultural practices, creating a fascinating contrast to mainstream holiday celebrations in the state.

Despite their small numbers, these Orthodox enclaves have tenaciously preserved their traditions, keeping their distinct holiday practices alive throughout the decades. The persistence of these communities is remarkable given their size. As late as 1963, the two Orthodox churches in Wilmington had a combined membership of only about 235 people. Just two years later, in 1965, Jim Parks reported in The News Journal that the Greek Orthodox congregation—which served all of Delaware and parts of nearby New Jersey—still consisted of only about 400 families.

Orthodox Christianity’s history in North America dates further back than many realize. Ukrainian missionaries were present on North American soil as early as 1759, in Alaska, which was then part of Russia. This early Orthodox presence paved the way for later waves of immigration, including the diverse group of Greeks, Ukrainians, Russians, Bulgarians, Hungarians, Montenegrins, Serbians, and Romanians who arrived in Delaware in the late 19th and early 20th centuries. Their reasons for emigrating included economic hardship, political instability, and, in some cases, religious oppression, particularly for those who belonged to Old Believer communities (a conservative sect within Russian Orthodoxy that faced persecution after refusing to accept church reforms in the 17th century).

In 1890, the first known Greek immigrants arrived in Wilmington. They were the Tsagares brothers, Panagiotes and James. Delaware’s Greek Orthodox presence in 1909 was still so small that no local services existed. The Evening Journal reported that the few Greeks in Wilmington had to travel to Philadelphia to attend that city's sole Greek Orthodox church. However, by 1910, we see the establishment of St. Michael's in Wilmington, marking the beginning of a more permanent Orthodox presence in the state (The Evening Journal, 1910).

In its early years, St. Michael’s was formally known as the Russian Orthodox Greek Catholic Church of St. Michael’s the Archangel, indicating its support of a wide swath of Christian believers. A 1916 Morning News article reported that "Russia, Servia, Montenegro, Bulgaria, Greece, and Roumania observed the holiday yesterday, and natives of those countries residing in this city took the day off and celebrated in proper fashion." Note that the spellings of some countries differ from today's usage—"Servia" for Serbia and "Roumania" for Romania, for instance. The article also mentions that all these ethnicities fell under the description "Ruthenian," a term not commonly used today.

The Ukrainian community began arriving in Wilmington in the 1920s. They quickly organized into two distinct groups: an Orthodox community and a Catholic community. The Orthodox group formed a congregation in 1928 and, a decade later, built Sts. Peter and Paul Church on S. Heald Street in South Wilmington.

Meanwhile, St. Nicholas Russian Orthodox Church served the Ukrainian Catholic community. Russian Orthodox immigrants established St. Nicholas in 1915, and the congregation initially met in a converted row house on South Claymont Street. As the congregation grew, they built a larger church in 1933.

One of the most distinctive features of Orthodox Christianity worldwide is its adherence to the Julian calendar for religious observances, while much of the rest of the world follows the Gregorian calendar. This difference is particularly noticeable during the Christmas season and has a significant impact on how Orthodox Christmas is celebrated in Delaware.

The majority of the population celebrates Christmas once, while the Orthodox communities celebrate it again according to their calendar. In Delaware, as in many places where Orthodox Christians live alongside other communities, the first celebration occurs on December 25th according to the Gregorian calendar, observed by the general population. The second celebration takes place on January 7th (Gregorian calendar), which corresponds to December 25th in the Julian calendar, and is observed by the Orthodox communities.

This dual celebration is vividly illustrated in a January 7, 1910 News Journal piece: "'Kula Christouyena.' 'Ke emes ossaftos.' Wherever two members of the Orthodox Greek Church meet today, these salutations will be exchanged between them, as they are the Greek equivalent of 'Merry Christmas' and 'the same to you.' According to the Julian calendar, today is Christmas Day for the Orthodox Greek Church, a celebration in which not only the Greeks of this city, but also the Russians, Roumanians, Montenegrins, Servians, and a few Hungarians will take part."

Over time, some Orthodox churches in Delaware have adopted the Gregorian calendar for Christmas celebrations, while others have maintained the Julian calendar tradition. By 1973, this split was clearly defined: "Some Eastern rite Orthodox churches will not be celebrating Christmas Tuesday, but will use the Jan. 7 date for the Nativity feast. That will be true in Sts. Peter and Paul Ukrainian Church, 1436 Philadelphia Pike. However, both St. Michael the Archangel Orthodox Church, formerly the Russian Orthodox, and Holy Trinity Greek Orthodox Church, will observe the Dec. 25 date, their priests said." (The News Journal, 1973)

This evolution in calendar usage reflects the ongoing negotiation between maintaining traditional practices and adapting to the broader American cultural context. The calendar differences not only affect the date of Christmas celebration but also influence other related observances. For instance, Epiphany, which is often nicknamed "Little Christmas" in Orthodox traditions, is celebrated at different times depending on which calendar a church follows. These calendar differences add a unique dimension to Delaware's holiday season, effectively extending the Christmas celebration period.