Most, if not all, of the concepts used in modern microprocessors where developed many years ago during the early years of computing. Since then we have basically rediscovered/adapted/refined them.
1959 - IBM 7030 Stretch
Interrupts, Memory Error Detection and Correction, Memory Interleaving, Memory Protection, Multiprogramming, Pipelining, Instruction prefetch, Operand prefetch, Speculative Execution, Branch prediction, Write buffer, Result forwarding
1962 - Burroughs D825
Symmetrical MIMD multiprocessor (first 4 core computer ;-)
1962 - Atlas computer
Virtual Memory, paging
1964 - CDC 6600
Multiple functional units, out of order execution, multi-threading
1964 - Illiac IV
Frst SIMD computer
1964
IBM begins design of the Advanced Computer System (ACS), capable of issuing up to seven instructions per cycle. (project scraped in 1969)
1965 Maurice Wilkes
Cache memory
1967 IBM360/91
Dynamic instruction reordering, reservation station, register renaming
1968 IBM 2938 Array Processor
Precursor of VLIWs in the 80's which are the precursors of the Intel Itanium
1969
Work begins at Compass Inc. on a parallelizing FORTRAN compiler for the ILLIAC-IV called IVTRAN.
Honeywell delivers first Multics system (symmetric multiprocessor with up to 8 processors).
1971 - Intel 4004
Has none of the above advancements, but its often cited as the first microprocessor (it's actually the second, but that is another story). Microprocessors will rediscover all of the above concepts during the 90's and 2000's but in fact there is nothing new under the sun. Everything we know today in microarchitecture has its roots more than 50 years ago.