The first bib overalls, referred to as "slops," were created in the early 1700s, they were reserved for the working man and were considered a symbol of low class. These overalls, were in fact, what we would consider trousers or pants today. The trousers were mostly seen as a working class symbol until the Regency Era of Great Britain when trousers became more accepted amongst the upper classes due to the transition to the Victorian Era. The US army would consider trousers overalls until the start of the Mexican War.
The first “modern” examples of overalls appears around the 1830s. Many photographs and painting clearly show that the trousers are sewn together with a top piece, considered an "apron" or "bib," which reveals to us that this is the first instance of a pair of "modern" overalls that we're used to seeing in this day. The overalls were always two pieces, a bib being sewn to a pair of trousers but when the 1850s rolled around, they became a single piece and were worn over the trousers. Specific colors and patterns slowly become standardized for the different types of working class. White was reserved for painters (most colors they painted were white so the stains wouldn't show up on their overalls), pin stripped for rail road workers, and various blue shades for the rest of the working classes.
Overalls were a mass produced item of clothing with the first commercial “do-it-at-home” patterns for these garments coming out in the early 1870s. The straps were fairly narrow and could have been either stitched or buttoned at the rear and at this time it seems that pre-1874 overalls usually have a button instead of a buckle to secure the straps in place on the front of the chest.
The one-piece work overall arrived in 1891 to fit over a shirt or vest and trousers. The most common material for overalls for this period was going to be denim and, to a lesser extent, some sort of waterproof material. The slits tended to be reinforced to prevent any tearing due to strain. The garments for this time period always had two patch pockets in the front below the waist and two patch pockets on the rear. Patch pockets on the bib were also common but were much smaller than what is reproduced these days.