When a lack of vital records and other documented proof of our ancestors' lives leads us to dead ends (or brick walls, the term commonly used in genealogy) an easy search in an online archive of newspapers could help fill the gaps.
Our ancestors used the newspapers the way we use phones, televison, and social media. In fact, the "personals" section of a 120 year old paper reads much the way our modern day Facebook newsfeed does. If someone was visiting family from out of town, if someone was sick in the hospital, if someone was celebrating a milestone birthday it was often listed in the personal ads of the local newspaper.
The newspaper was the primary way businesses were advertised. If you believe that your ancestor owned or operated a business, an ad for the establishment in newspaper archives may verify the information.
According to family stories, two of my great-great grandfathers (on different sides of my family tree) owned and operated bars. Using newspaper archives I was able to find ads for both of their businesses that I would not have found otherwise.
A good place to start, and the archive I have had the best luck with is Newspapers.com.