The 1983 edition of Motorola's "Linear and Interface Integrated Circuits" (Series D) catalog contains an "Advance Information" data sheet for the MC34063 so that is likely to be around the time of introduction. That catalog also contains several other switching regulator ICs. Among those were MC3420 and MC1723 (below).
My first switching regulator circuit was around 1982 using an LM723 (National Semiconductor) which could be used as a linear or a switching regulator. This part was also available from Motorola as MC1723.
Both the LM723 and the MC34063 are still available!
In 1968, Motorola published "Semiconductor Power Circuits Handbook" which contains several discreet switching regulator circuits. We have a first-edition copy where I work ... a nice little book.
For more on the history of switching supplies:
https://en.wikipedia.org/wiki/Switched-mode_power_supply#History
After quite an exhaustive search, I have been unable to determine when the 5.8 GHz ISM band was initially allocated. Although one document implies it was done in 1947 along with the 2.45 GHz ISM band, the ITU document you referenced makes it pretty clear the only ISM bands allocated back then were 13.66 MHz, 27.320 MHz, 40.980 MHz, and 2.45 GHz as you stated.
In 1985, the 2.45 GHz ISM band was opened up to general communication, but requiring the use of spread spectrum techniques to reduce interference from other activities on the band.
In 1997, the same thing was done for the 5.8 GHz ISM band, due to the potential for severe RF congestion in the 2.4 GHz band.
So the 5.8 GHz ISM band was initially allocated sometime in the 50 year span between 1947 and 1997. Not very precise, sorry.
In the 5.8 GHz band, 5.725–5.875 GHz is specifically allocated to ISM and also used for wireless LAN (802.11/a).
BTW you wouldn't want to use the 4.9 GHz, as you wouldn't want to use a band that is the second harmonic of devices in the the busy 2.45 GHz (although all devices must be tested that they produce no harmful emissions for FCC certification, so there should theoretically be no interference).
Besides avoiding congestion in the 2.45 GHz band, using the 5.8 GHz band allows for higher data rates.
However operating in a higher frequency band increases the noise level, obstacles and walls are more opaque to transmissions and a higher bit rate requires more SNR (Signal Noise Ratio), which means a reduced range compared to 2.4 GHz products.
Some of the products that specifically make use of the 5.8 GHz band are baby monitors, cordless phones, and cameras (mentioned, for example, here and several other documents). It's not clear to me whether cordless telephones should be classified as ISM or communications -- I guess it depends on whether they use spread spectrum or not.
I also found this digital microwave radio that has a bandwidth of 39 MHz and a range of 45 Km. It is a wireless extension of a STM-1 fiber optic network. So this would definitely be an ISM application.
Research in using RFID technology in the 5.8 GHz ISM band is being carried out also.
Best Answer
Bob Widlar designed the first monolithic IC linear regulator, the µA723 for Fairchild Semiconductor in 1967, and later designed the LM100 for National Semiconductor.
This is the same guy who designed the first monolithic IC op-amp, the µA702, also for Fairchild.
Sadly, you're not going to find many online references to these things, since they're all long-obsolete, replaced by jellybeans nearly as ancient.
Now, the 723 isn't a three-terminal regulator. It's adjustable and more complicated to use than the later LM117/317, which essentially replaced it. The first monolithic three-terminal fixed regulator is probably the LM109/309, released in 1969.