This is a briefly made timeline of the most important mythos oriented happenings in BSG. I know I’ve made mistakes, will append as pointed out by others.
BSG TIMELINE
1.)Life on Kobol evolved into recognizably human shapes
2.) As the humans advanced they decided to create artificial beings, the cylons.
3.) The cylons, having reached an evolutionary point in which they were cognizant enough to realize their own enslavement, rebelled.
4.) Presumambly some kind of conflict or war drove the cylons and other humans to leave Kobol.
5.) 12 tribes search for home
6.) cylons search for their own home
7.) Presumambly, the clyons attempt to develop flesh bodies.
8.)Cylons achieve this end.
9.) Ressurection is invented
10.) cylons find earth
11.) 12 tribes found the coloines
12.) Cylons begin to procreate biologically
13.) Cylons are warned of imminent attack (presumambly from the humans?)
14.) Ellen, Tyroll, Tory, Anders and Saul collaborate to revive ressurection technology in the hopes of surviving the warned-of attack.
15.) Ellen finally makes the breakthrough needed to reinvent ressurection.
16.) Shortly thereafter, Earth is frakkin’ nuked.
17.) The Tighylons revive on board the orbiting ressurection station.
18.) They set out to warn the humans of instigating another cycle.
19.) thousands of years pass, at subliminal - but relativistic - speeds time slows for the tighylons as they set out in search of the 12 tribes of humans.
20.) The people of the 12 colonies form a federated government.
21.) They create their own versions of cylons
22.) they rebel
23.) Cylon War Begins
22.) Cylons begin to search for ways to be more human like.
23.) cylons begin kidnapping humans for research
24.) Their research yeilds the birth of the Old Clyon Hybrid.
25.) tighylons reach the other cylons
26.) Adama encounters Old Cylon Hybrid
27.) tighylons promise to share their organic technology with the Colonial cylons if they end the war.
28.) Colonial-Cylon treaty signed.
29.) Cylons retreat beyond the treaty line.
30.) Tighylons work with Larry style Centiruions to build the skinjobs.
31.) Cavil is created in the likeness of ellen’s father.
32.) Cylons 2-6 are created.
33.) Model #7, Daniel, and the Eights are created.
34.) Cavil grows jealous of Ellen’s love for Daniel.
35.) Cavil corrupts the amniotic tubs Daniel(s) are growing in and corrupts his genetic code
36.) The Final Five no doubt object to this behavior
37.) Cavil suffocates them.
38.) Cavil selectively controls their resurrection, implants false memories in them.
39.) Saul is released into the colonies
40.) Tory, Anders, and the Chief are released in due time, many years after the cylon war ended.
41.) Cylons continue to propagate and desire vengeance.
42.) Colonial holocaust is planned.
43.) Sleeper agents are set.
44.) Caprica Six gains the security code from Baltar.
45.) Colonial holocaust
46.) Events of the miniseries
47.) Ellen is released into the fleet.
48.) Boomer fears she is a Cylon.
49.) Kobol found.
50.) Boomer shoots Adama, then is killed herself.
51.) Starbuck encounters Anders on Caprica
52.) Eventually, Anders joins the fleet.
53.) Crew settles down on New Caprica
54.) A year passes
55.) The Cylons find them, and occupation begins.
56.) Saul Tigh is imprisoned and tortured.
57.) Tigh’s eye says goodbye.
58.) Ellen begins sleeping with Cavil to get Saul released.
59.) The swhirl.
60.) Saul is released.
61.) Ellen is forced to betray the resistance
62.) Saul poisons Ellen.
63.) Ellen resurrects aboard a baseship far away.
64.) Ellen remembers everything.
65.) Galactica and Pegasus rescue the fleet.
66.) Tyroll discovers the temple of the five down on the Algae planet
67.) Standoff, D’anna discovers the faces of the five, dies.
68.) Super nova leads the fleet towards a new direction in their search for Earth.
69.) Malestrom - Kara dies.
70.) Events of Crossroads - Tigh, Tory, Anders, Tyroll discover that they are cylons. Crazy Bob Dylan Music.
71.) Kara returns, believes she knows where Earth is. Sets out on poo barge with Anders and co.
72.) Cylons discord begins to grow.
73.) Cylon civil war
74.) Kara returns with a rebel basestar.
75.) Form of truce between the fleet and rebel baseship. Plan to blow up the hub is formed
76.) Basestar hybrid abducts Roslin
77.) Crazy frakkin’ hallucinations, Roslin becomes a bit better of a person.
78.) Hub destruction plan is still go.
79.) Cylons and Colonial pilots team up to take out the hub.
80.) Hub is destroyed.
81.) Resurrection, at least for the Significant Seven (or as we must now call them, the Especially Important Eight) ends.
82.) Earth is found in Kara’s viper.
83.) Earth turns out to be craaaaaaaaaap.
84.) Poor Dee 
85.) Gaeta’s disembodied leg drives him to mutiny.
86.) Anders is shot during the mutiny.
87.) Mutiny is ended, Gaeta/Zarek are executed.
88.) Anders sees what lies in between life and death, remember everything.
89.) He explains the history of the final five, to some extent.
90.) Ellen escapes her lobotomy with Boomer.
