Final answer:
Irish Spring soap was introduced during an era when toilet soap became widely available and advertising campaigns were pivotal in promoting soap brands. While the exact introduction date of Irish Spring isn't specified, it follows in the legacy of prominent soap businesses that utilized marketing innovations and mass production.
Step-by-step explanation:
Introduction of Irish Spring Soap
Irish Spring soap was first introduced during a period when toilet soap was popularized via industrial manufacturing and wide-reaching advertising campaigns. Large soap manufacturers that played a key role in the soap business, such as Lever Brothers, which became Unilever, were among the first to employ large-scale advertising campaigns. While the details on Irish Spring's initial introduction may not be provided in the historical context, the lineage of soap development and marketing strategies can be linked to its eventual presence in the market. Innovation in the soap industry has spanned several centuries, with early small-scale production giving way to large businesses and industrial soap makers like Benjamin T. Babbitt and B.J. Johnson's Palmolive, both notable for their marketing strategies and product development.