Interest in the styles of earlier periods was the primary characteristic of 19th century architecture from Europe to Boston to Lowell. For example, in the first half of the century, the Federal style, inspired by the new federal government, borrowed its form from the English Adam style while the Greek Revival style borrowed its features from classical Greek architecture. In the second half of the century, architectural design became more eclectic with several historic styles being popular at once. Italian villas inspired the Italianate style, French Second Empire buildings inspired the Second Empire or Mansard style, and English Tudor cottages were the inspiration for the Queen Anne style.
It is important to note that buildings are not always clearly representative of a single style but often incorporate elements of several styles. Since architectural styles evolved gradually, it is not unusual to find buildings that exhibit details from several different styles. Not every historic building is a "Colonial" or a "Victorian" as those are umbrella terms, often encompassing several styles and broad periods of time.