The Atlas Model Railroad Company, Inc of Hillside, New Jersey, began making track and related model railroad products in 1949. The Atlas Tool Company was founded in the 1920’s by Stephan Schaffan, but they didn’t make any train related items until after World War Two. Their HO and n gauge track and products are standard around the world. They also produce a full line of HO and N gauge rolling stock, locomotives, buildings and more.
In 1972, Atlas flirted with the O gauge market, producing two diesel locomotives and a modest line of rolling stock. Their O gauge trains were DC powered and ran on two rail track. But the rolling stock came with Lionel compatible knuckle couplers and tinplate wheelsets. The line did not fare well and was dropped soon thereafter.
In 1997, Atlas reentered the O gauge market, offering prebuilt buildings. A track system followed, this time being three rail track such as is used by Lionel, MTH, and others. Freight cars came in 1998. Their dominant products are still in the HO and N gauge markets, but early remarks show that operators like the new O gauge products as well.