Ah, finally a CPF question I can answer. Sit down and grab a drink. Stock (Everready, Ray-o-Vac, etc) flashlights were all that was used until the very late '60s, and were still in wide use through the '70s.
Deputy Don Keller designed the Kel-Lite around 1968. His models were basically common flashlight components (but with an improved bulb holder) in a heavy aluminum housing. He left the company in 1972-73. Around '76 a new external switch was introduced. Different sizes and styles of lights were made throughout. The company went under in 1983.
After Don left Kel-Lite he designed the B-Lite for Bianchi in the mid '70s. Better made then the Kel-Lites but weak switch electrics. The design was changed in 1984 but then they stopped production.
He also did the Pro-Light for another company. Similar to B-Lites, but they could be had in all-plastic or part-plastic versions. Could be converted to rechargables with a special sleeve. Lasted into the early '80s.
Cut to Streamlight. They were making their first rechargable lights around 1975 or so. They bought what was left of Kel-Lite in '83/84 and produced a line of C/D lights using the name. They were later sold as Excalibers until a lawsuit from Mag put a stop to that line around 1990.
Back to Mag, they came out with their first light in 1979. It's basically the same thing they sell today. It was an instant hit, partly due to the better switch (compared to everything that came before) and the focusing mechanism (which is of debatable utility), and partly due to Maglica's high-speed manufacturing. Better lights for less money. The Mini-Mag and Magcharger were introduced in the mid '80s. Also in the mid '80s they made the Vari-Beam, a model sold to car mechanics.
Along with all the big brands, in the '70s and '80s there were the Code-4 and Smoke Cutter lights. First sold by LA Screw, then bought by GT Price, which sold out to Nordic a while back. Also in the '80s was a whole line of different Brinkmann lights. The 5-3-2 is still made and is basically the Code-4 design. Keller also designed the first Legend light for Brinkmann. Around 1970 there was the Tru-Grit, a Kel-Lite knockoff. In the late '80s a gun company called Grendel made a weird 8AA flashlight that didn't last long. In the early '90s Cold Steel made a 7AA light called the Brute. Also didn't last long.
That's the short version if you can believe it. Mag came along towards the end of the police light arms race. From then on Mag sold most of the primary cell lights, Streamlight sold most of the rechargables. Surefire came out with the first lithium one around 1988. In case you're wondering, all the above pics are from my collection which by now has gotten quite a bit bigger. I'm still hunting for more examples, by the way, since I only have a fraction of what was sold.
All your flashlight are belong to us.