In 1467, the Moravians separated from the Roman Catholics and sought to live a life of the purest conduct. They were descendents of Martin Luther’s Protestant movement. Although the religious group has been referred to under various names, the English-speaking world has adopted the term Moravian, while the Moravian tend to refer to themselves as the "Unita Fratum" (Witcraft, 1927). The Moravians originally settled in the mountains east of Prague and then moved into areas of Moravia and Bohemia as well (Hugh Moore Historical Park and Museums). After the Thirty Years War, the Moravians began to be repressed by the Catholics. The repression motivated the Moravians to seek refuge in the New World, where they could establish their own missionaries (Smaby, 1988). The German nobleman Nicholas Ludwig, Count of Zinzendorf, was very influential in helping the Moravians meet this goal. In fact, he even helped them to receive free passage over to the colonies (Witcraft, 1927).

The first attempt at Moravian settlement in North America occurred in Georgia, but the Moravian beliefs were not accepted in this new colony. Therefore, they sought to settle elsewhere. In 1740, they befriended the Methodist preacher George Whitefield and helped him to build a school in the town which Whitefield later called Nazareth, near the Fork of the Delaware. Religious disputes caused the friendship between the Moravians and Whitefield to end sharply, but the Moravians refused to leave Nazareth when asked (Witcraft, 1927).

In 1741, they purchased a 500-acre plot of land where Monocacy flows into the Lehigh River. This site was known to the Indians as "Monogassi" (Meyers, 1981). The Moravians started to build their town, which would be the center of their missionary activities in America (Smaby, 1988). On December 21, 1741, Count Zinzendorf arrived at the new settlement. Since the colony was unnamed, it was decided by common consent to call it Bethlehem (

Witcraft, 1927). The lands of Nazareth were also bought later that year by the Moravians due to the financial difficulties of George Whitefield (Hugh Moore Historical Park and Museums).
The Moravians in Bethlehem divided themselves into various groups called choirs. Age, sex, marital status, and spiritual seniority separated the members of these groups. Choir members did various things together such as eating, praying, working, and providing support for one another (Hugh Moore Historical Park and Museums). The people of the community gave time and labor in exchange for food and shelter, something they called the "General Economy" (Smaby, 1988). Their motto was "We pray together, we labor together, we suffer together, we rejoice together." The church was the center of the community and the Moravians sought to bring their religious beliefs to others in the area such as the Indians (Hall and Hall, 1982).

The Moravians were very interested in both religious and aesthetic matters such as visual arts and music. Besides this, they were very accomplished as architects and engineers. They developed large stone and brick buildings that are still standing today (Hall and Hall, 1982). Two industrial sections of Bethlehem were also established by the Moravians along Monocacy Creek. These industrial buildings were separated from the residential buildings, although they were made with the same limestone and red brick arches as those of the residencies. They were even created with the same amount of aesthetic detail. The common features unified the industries and the residences (Smaby, 1988).

In Bethlehem in 1754, the Moravians developed the first pumped water system in America (Hall and Hall, 1982). Maps of the area suggest that the Moravians may have placed the industries purposely near the water. Some of the industries such as the oil mills utilized water for their power. Others like the wash house or the bleach house needed water as an ingredient. Traditionally, industries have used water for waste removal, as most of these companies did. It is likely that the wastes flowed directly into the Monocacy Creek. Since the Monocacy Creek flowed directly into the Lehigh River, this waste removal would have decreased the water quality in both the Creek and the River (Smaby, 1988).

The communal nature of the Moravian settlements, including both Bethlehem and Nazareth, began to dissolve in 1762 when the General Economy was removed. The Revolutionary War provided further strain because it was not in the Moravians nature to fight; therefore, they refused to bear arms. This caused other Lehigh Valley Patriots to distrust them, although the Moravians did help in treating wounded soldiers and providing supplies. The Revolutionary War brought them into contact with other communities in America, namely, different secular communities. This enabled the Moravians to incorporate other communities into their daily lives and their exclusive religious communities eventually dissolved (Hugh Moore Historical Park and Museums).