The phrase "was of" can be substituted with a variety of synonyms depending on the context of the sentence. Some options include: "belonged to," "originated from," "came from," "formed part of," "was a part of," "was associated with," "was connected to," and "was linked to." These alternatives can help to enhance the overall clarity and specificity of a sentence, providing the reader with a more detailed understanding of the subject matter. Choosing the right synonym can also help to vary sentence structure and avoid repetition, making writing more engaging and interesting to read.