This timeline is based on Earth-A ('A' is for Alternate) which is home to 
the Lawless League of America.
 


1938
============================
 Thunderbolt travels back in time to his own earth and somehow causes Ripper 
Jones to take the place of two-year-old Kal-El as his rocket lands on Earth.


1940's
============================

 Thunderbolt travels back in time to his own earth and causes Bill Gore's 
parents to be murdered.  He also affects Gore's psychology to instill 
superior self-discipline causing the orphaned lad to train himself to 
one day be the Batman.
 Superboy begins his period of juvenile delinquency in Smallville.
 Oliver Queen encounters Superboy, resulting in the loss of his 
right arm.  (speculation based on Adventure Comics #258)
 Superboy encounters Aquaboy, the encounter probably being fatal for 
the latter. (speculation based on Superboy #171)
 Bill Gore visits to Smallville with his guardians and briefly becomes 
the Executioner.  Superboy may have used a special device to show him 
his future as an adult, but with Gore's permission, used a device to 
erase his memory of what he saw.  (speculation based on Superboy #182, 
World's Finest Comics #271)

1954
============================
 Superboy moves to Metropolis and begins his career as Superman.
 Thunderbolt travels back in time to his own earth and causes Bruce Wayne's 
first public adventure (the case of the chemical syndicate) to be his only 
case as he returns to being a millionaire playboy.  Perhaps due to the lack 
of Wayne's prior contact with a heroic Superboy, his Bat-Man costume resembles 
that of his Earth-2 counterpart at the beginning of his career.
 Bill Gore dons the suit of the Batman and begins his criminal adventures. 
(Justice League of America #37-38).

1955
============================
 Eddie Orson traveled back in time and is placed in Martian Manhunter's 
arrival to Earth. He then becomes Martian Manhunter of Earth-A. 
(Justice League of America #37-38).
 An Amazon warrior enters the Man's World as an ambassador and is 
immediately slain by an invisible Eddie Orson.  (speculation based 
on Planetary #10)

1956
============================
 After the Thunderbolt sends Race Morrison to the time of Silver Age 
Flash's origins, it causes Race Morrison to be substituted for The Flash. 
(Justice League of America #37-38).

1959
============================
 Monk Loomis travels back to this time and gets the ring of Abin Sur to 
become Green Lantern of Earth-A. (Justice League of America #37-38).

September 1961
============================
 When time-travelling, Barney Judson appears at the time of Ray Palmer's 
scientific discovery. He starts using Ray's size-changing belt and becomes 
The Atom. (Justice League of America #37-38).

1963
============================
 Zorina, finding her father Zor gone and his house in a shambles, discovers 
his diary, reads how he first learned to work magic by speaking his commands 
backwards, and resolves to go on a quest to find him.  She encounters the 
Atom and Batman on her search (speculation based on DC Special Blue Ribbon 
Digest #5, Seven Soldiers: Zatanna #4; see Notes).

August 1965
============================
 The Earth-1 Johnny Thunder knocks out his Earth-2 counterpart and takes 
hold of his Thunderbolt. He orders the Thunderbolt to go back in time and 
make the Justice League cease to exist. After that, he encounters members 
of Justice Society of America and tells the Thunderbolt to send his criminal 
friends back in time and places them to the area of The Justice League 
member's origins which causes the creation of Earth-A universe.
 Other creations of the evil Johnny Thunder include the monstrous Medusa-Man, 
whose face can turn whomever sees its face to wood; Absorbo-Man, who can 
absorb any super-powers and use them to his advantage; and Repello-Man, 
who can repel any force directed at him.
 Justice Society of America members defeat the evil Johnny Thunder and 
undo the damage to Earth-1's continuity, effectively "breaking" Earth-A. 
(Justice League of America #37-38).

1997
============================
 Jakita Wagner of Planetary visits the remains of Earth-A.  (Planetary #6)




NOTE:

Since Zor is a renegade time-tamperer, and he created Zorina by temporal 
tampering, I guessed he might have chosen to do so on Earth-A.  The 
text from the entry is paraphrased from Dark Mark's Zatanna Index.  Her 
search for Zor was sadly truncated by the events of JLA #38.

Timeline by Nathanial Parkson, edited by Mikel Midnight