Historians' TIMELINE of ancient Tamil Kings of Sangam works

[senthilkumaras]

As far as we have collected from sangam literature,
the Timeline of ancient Thamizhagam is as follows[years in bold are historically correlated well identified dates]

TO READ AS :[E]=EMPEROR OF HIS TIME;
FIRST NAME+-SURNAME ACCREDITED NAME : YEAR OF ACCESSION TO THRONE: CHANGE OF CAPITAL TO:
[E]kaai cina vazhuthi 9800 B.C.E.-THENMARUTHAM
nedumeen thizhigan
vael'meen kaavan
..........
kadungoan 5400 B.C.E.-KU'ADAM (ALAIVAAI)
ilanthirai vazhuthi 5370 B.C.E.
...........
vaandroarchezhiyan 3100 B.C.E.-KOR'KAI
mukkaavan vazhuthi 3020 B.C.E.
...........
[E]alaivaai agazhch chezhiyan 2845 B.C.E. -old remaining land of the partially submerged city of KU'ADAM,then an island
[E]thamizhi ,thizhigan 2800 B.C.E.
[E]nar'seyan vazhuthi 2750 B.C.E. -KOR'KAI because the remaining KU'ADAM too submerges,
porkaippandyan 2400 B.C.E.
ol'vaenmaruthan 2350 B.C.E. -MAN'AVOOR
...........
[E]yaazhthi kaavan 2300 B.C.E. -THIRUCHCHEERALAIVAAI
kaavan thizhigan 2275 B.C.E.
mudaththirumaar'an 1700 B.C.E.-MATHURAI
ilanambi maar'an 1665 B.C.E.
...........
[E]nediyoan, , vaimbalamba nindra,munneer vizhavin , perungalanediyoane 510 B.C.E.
thizhigan
chezhiyanvazhuthi
......
.
neduvazhuthi
[E]nambi, , pandyan arivudai 360 B.C.E.
paan'arvazhuthi
nedunjezhiyan
kochchezhiyanaval'an
perunjezhiyan
[E]poothappaan'diyan ollaiyur thandha poothappaan'dian 150 B.C.E. ....
....
[E]nambi nedunjezhiyan 76 B.C.E.
semmaaran 35 B.C.E.
nedunjezhiyan , aryapadaikadantha, 10 B.C.E.
[E]perumpaeyar vazhuthi ,karungai ol'vaall', 25 C.E.
nedunjezhiyan , cithiramadathu thunjiya 85
peruvazhuthi , velliambalathu thunjiya 110
nanvazhuthi , koodakarathu thunjiya 118
nanmaar'an , ilavanthigaipalli thunjiya 121
[E]nedunjezhiyan , thalaiyaalangaanaththu 125
cheru vendra pandyan
ukiraperuvazhuthi, kaanapaereyil erindha 165
[E]peruvazhuthi , palyaagasalai mudhukudumi 200 C.E.

CHOZHA KINGS
mudiko,mael,kaal'aiyam,thagaiyan 2750 B.C.E.-POOMPUGAAR
ilangokkeezhkaalaiyanthagaiyan 2730
[E]nedunjaetchozhathagaiyan ?2710
keezhnedumannan 2680
kaal'andhagan 2665
ilangeezhnannan ? 2645
[E]kaal'aiyangudingyan ?2630
nedungaal'andhagan 2615
vaengaineduvaelvaraiyan 2614-2615
vaetkaal'kudingyan 2600
il'avaelvaraiyan 2590
[E]sibi vendhi 2580 B.C.E.
[E]parunonjichaamazhingyan 2535
vaeqratrtrichembiyachozhan 2525
[E]saamazhichozhiyavael'aan 2515
uthivengaalaithagan 2495
nannanthatkaal'aithagan 2475
velvaenmin'di 2445
nedunjembiyan 2415
[E]nedunonji vendhi 2375
[E]vaelpaqratrtri 2330
perunthoan'nonji 2315
kudikopungi 2275
perungoeppoguvan 2250
koeththatrtri 2195
[E]vadisembiyan 2160
[E]aal'ampoguvan 2110
nedunjembiyan 2085
perumpaeyarpoguvan 2056
kadunjembiyan 2033
[E]nedunkathan 2015
[E]parunakkan 1960
van'isembiyan 1927
udhachir'amondhuvan 1902
perunkaththan 1875
[E]kadunkandhal'an 1860
nakkamonjuvan 1799
maar'kovaelmondhuvan 1785
ven'kaandhal'an 1753
perunakkan thatrtri 1723
vaerkaththan 1703
[E]ambalaththu irumundruvan 1682
kaarimondhuvan 1640
ven'nakkan thatrtri 1615
vaqroat cembiyan 1590
[E]maar'kochunthuvan 1565
[E]vaerparunthoan'mundruvan 1520
[E]udhankaththan 1455
[E]kaarikosunthuvan 1440
vendrinungun'an 1396
mondhuvan vendhi 1376
kaandhaman 1359
mundruvan vendhi 1337
kaandhaman 1297
monjuvan vendhi 1276
an'isembiyan 1259
nungun'an vendhi 1245
maar'kopperum cenni 1229
monjuvan nanvendhi 1180
[E]kopperunarchenni 1170
monthuvanjembiyan 1145
narchenni 1105
caetchembiyan 1095
nakkarchenni 1060
[E]parunjembiyan c.1045
venjenni 998
musugunthan 989
maar'kopperunjembiyan 960
nedunjenni c.935
thatchembiyan 915
ambalaththuiruvaerchembiyan 895
kaarikochenni 865
venvaerchenni 830
[E]kaandhaman , 788
perunjenni
kaandhal'an 721caetchenni 698
van'inungun'an 680
mudhusembiyan vendhi 640
peelanjembiyachchozhiyan 615
maeyangadungo 590
[E]thiththan 570 -UR'AIYUR
perunarkilli porvaiko 515
kadumundruvan 496
nedunjembiyan 495
nakkanaranjozhan 480
thevvangochozhan 465
naranjembiyan 455
[E]nakkampeelaval'avan 440
iniyanthevvanjenni 410
var'cembiyan 395
kopperunjozhan 386
narkilli mudiththalai 345
ambalathuirungochchenni 330
perunarkilli 316
kochaet cenni 286
[E]ilanjaetcenni cerupazhi erinda, 275
pamuloor erindha
neithalangaanal
nedungopperunkilli 220
[E]cenni ellagan (elder brother of Ellaalan who conquered Srilanka 205-POOMPUGAAR
perungilli 165
[E]kopperunjozhiyavil'anjaetcenni 140
perunarkilli mudiththalaiko 120-UR'AIYUR
ilamperunjenni 100
perungilli vendhi 70
nalangilli caet cenni , ilavanthigaipalli thunjiya 45
vaenalangilli 15 B.C.E.
ilanjaetcenni , uruvapakraer 10-16 C.E.
[E]peruval'aththaan , karikaalan 31-POOMPUGAAR
perunarkilli , vaerpaqradakkai 99
perunthirumaval'avan ,kuraapalli thunjiya 99
nalangilli 111
[E]perunarkilli , kulamutrtraththu thunjiya 120
perunarkilli , irasasuyavaetta 143-URAIYUR
vaelkadunkilli 192
kochengan'aan 220

CERA KINGS

[E]maavalicheran c.1150 B.C.E.-NAR'AVU
[E]parasuramaraadan c.1050 B.C.E.
[E]uthiyan cerlaadhan , perunjoatrtru c.900 B.C.E.
.........
[E]nedunjeraladan , imayavaramban 680
......
[E]ceral irumborai , naarmudi 300-VANJI(in his later years)
.....
[E]anthuvanjeral irumborai 130
perunjeralirumborai , ol'vaall' 100 B.C.E.
....
[E]kuttuvankoadhai 45 B.C.E.
kudakko ilanjeraladan 10 C.E.
perunjeraladan 40
kudako nedunjeraladan 99
[E]cenguttuvan , kadal pir'akkoattiya
vaelkezhu 99
selvakadungo , vaazhiyaadhaan 120
paalai paadiya
sikkarpalli thunjiya
[E]perungadungo , vaazhiyaadhaan 137
thagadoor erindha
marutham paadiya
maariven'ko 165
irumborai , kanaikkaal 198
CERA KINGS FROM THON'DI
kodhai maarban 120-THON'DI
maaandharanjeral 124
irumborai
maakkoadhai , kottambalathuth thunjiya 143 C.E.
[sources: Delineated timeline of ancient civilizations, Gerald Hugo & Lesley Wells,1974 with incomplete Pandyan line and Cera kinglines, Nakkeerar's Timeline of Tamizh Koodal Academies and Sumerian kinglist of Ur and Uruk.]

Most historians accept the timeline (historical dates) given in the ancient works like Mahavamso , Vedas,Chinese texts, Roman scripts and Greek texts and epics , eventhough they all are mixed with mythological and imaginary stories of their respective civilizations;
but how is that they do not look into the truth and narration of historical events without any adulteration of mythology in the ancient Tamilzh works like Puram,Agam,etc.
Is it because of the ignorance and inefectiveness of our Tamizh scholars are lack of documentation of such historical dates of events from our Sangam works due to carelessness or lazyness.
Kindly friends, put on your valuable thoughts.
thankyou;