This article is from the Nordic countries FAQ, by Antti Lahelma and Johan Olofsson, with numerous contributions by others.
1617
Karelia joined into Finland in the peace treaty of Stolbova
ending a hundred years of almost continuous wars with Russia.
1630-48
Finns fight in the Thirty Years' War in the continent. The
Finnish cavalry, known as hakkapeliittas, spreads fear among
the Catholic troops who're used to more orderly warfare.
1637-40 and 1648-54
Count Per Brahe as the general governor of Finland. Many and
important reforms are made, towns are founded, etc. His period
is generally considered very beneficial to the development of
Finland.
1640
Finland's first university founded in Turku.
1642
The whole Bible is finally published on Finnish.
1714-21
Russia occupies Finland during the Great Northern War. The
period of the so called "Great Wrath".
1721
The peace of Uusikaupunki gives Karelia to Russia.
1741-43
The "War of the Hats". Adventurous politics by the "Hat" party
leads to a new disastrous war with Russia and a new occupation
of Finland, known as "The Lesser Wrath", which ends in the
peace treaty of Turku in 1743.
1757
Storskifte, first reform of Swedish farming decided.
1766
The liberty of Press and "Offentlighetsprincipen" was declared
as constitution.
1808-09
"The War of Finland". Russia attacks Finland in Feb. 1808
without a declaration of war; Finnish troops retreat all the
way to Oulu, which forces Russians to leave a large part of
their army as occupation forces, giving the Swedish general
Klingspor superiority in force. A reconquest starts in June and
Klingspor receives several victories; however, the baffling
surrender of the mighty Sveaborg / Suomenlinna fortress on May
3rd and the fresh Russian troops received in autumn of 1808
force the Swedish-Finnish troops to retreat all the way to
Härnösand in Sweden. Once again Russia occupies Finland.
1809
In the diet of Porvoo, while the war still goes on, the Finnish
estates swear an oath of loyalty to Emperor Alexander I, who
grants Finland a status of an autonomous Grand Duchy, retaining
its old constitution and religion. A few months later the peace
treaty of Hamina (Fredrikshamn) is signed and Finland becomes
under Russian rule.
1812
Helsinki, being closer to Russia than the Swedish-oriented
Turku, is made the new capital. Karelia is joined to the Grand
Duchy as an act of goodwill.
1809-99
Finland prospers under the extensive autonomy and more liberal
conditions than in the rest of Russian Empire. National
identity and nationalism awakens.
1827
The great fire of Turku destroys most of the former capital.
The university is moved to Helsinki.
1835
The first publication of the Kalevala, the Finnish national
epic. It was collected by Elias Lönnrot from traditional
Karelian oral poetry, and became the most important source of
inspiration to Finnish nationalists when it appeared in its
final form in 1849.
1862
The first railway, between Helsinki and Hämeenlinna.
1866
Finnish becomes, alongside with Swedish and Russian, an
official language.
1899
Russia starts a Russification policy of Finland with the so
called "February manifesto". After the initial shock and
disbelief, a well-organized passive resistance follows.
 
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