This street originates in the 1882 plat of Bigelow’s Addition to the City of Seattle, filed by Jesse W. George (1835–1895) and Cassandra Eckler George (1840–1920) at the request of Isaac Newton Bigelow (1838–1922). As the Queen Anne Historic Context Statement explains,
In the early 1870s, the Denny and Mercer families gradually began to systematically subdivide their large land holdings on the south and east slopes of Queen Anne Hill. When a severe windstorm blew down thousands of trees in the north district in 1875, views opened up and land seekers turned their attentions beyond Belltown. Real estate speculators new to the territory arrived and began to buy up property on the crest of Queen Anne Hill. Some of these speculators also became developers, such as George Kinnear, or builder-developers, such as Isaac Bigelow.
Though its proximity to Boston and Lynn Streets suggest a tribute to Newton, Massachusetts, neither the Georges nor the Bigelows appear to have a connection to the state, so it seems this one should be chalked up to Isaac Bigelow’s middle name.
Today, Newton Street begins in Magnolia as W Newton Street at 30th Avenue W, and goes nearly half a mile east to 23rd Avenue W. There is then a two-block stretch from 15th Avenue W to 13th Avenue W in Interbay, and then the “original” Newton Street, which stretches almost a half mile from 1st Avenue N to Taylor Avenue N, followed by another two-block stretch from Dexter Avenue N to just past 8th Avenue N. On the east side of Lake Union, E Newton Street picks up again at Terry Pettus Park, just west of Fairview Avenue E, and goes ¼ mile to Boylston Avenue E and Lakeview Boulevard E. There follows another ¼-mile stretch from Broadway E to Everett Avenue E. East of there, Newton exists in a number of short segments through Montlake, and then enjoys a run of ⅓ of a mile from 37th Place E to 43rd Avenue E in Madison Park.