Agency: Who were the primary actors in Newark's rapid growth? What specific people, groups, or ideas can we credit
for causing the town's rise?

Seth Boyden and the ideas of manufacturing leather, railroads, and the first plastic.

Explanation:

Newark's rapid growth began in the early 19th century, much of it due to a Massachusetts transplant named Seth Boyden. Boyden came to Newark in 1815, and immediately began a torrent of improvements to leather manufacture, culminating in the process for making patent leather. Boyden's genius led to Newark's manufacturing nearly 90% of the nation's leather by 1870, bringing in $8.6 million in revenue to the city in that year alone. In 1824, Boyden, bored with leather, found a way to produce malleable iron. Newark also prospered by the construction of the Morris Canal in 1831. The canal connected Newark with the New Jersey hinterland, at that time a major iron and farm area. Railroads arrived in 1834 and 1835. A flourishing shipping business resulted, and Newark became the area's industrial center. By 1826, Newark's population stood at 8,017, ten times their 1776 number. The middle 19th century saw continued growth and diversification of Newark's industrial base. The first commercially successful plastic — Celluloid — was produced in a factory on Mechanic Street by John Wesley Hyatt. Hyatt's Celluloid found its way into Newark-made carriages, billiard balls, and dentures.