When french trappers arrived in today’s Montana in the 18th century, it was inhabited by the Crow, the Cheyenne, the Blackfeet, the Assiniboine (also known by the Ojibwe exonym Asiniibwaan ("Stone Sioux")), the Gros Ventre, the Salish and Pend d'Oreilles, the Chippewa and the Cree peoples. Many of them were annihilated in the Indian Wars of 1876-’77.
From the european point of view it became a part of the French colony of Nouvelle France and was sold in 1802 as a part of the Louisiana Purchase. The western part became a part of Oregon Territory. The areas east of the continental divide became the Nebraska and Dakota territories and had also been acquired by the United States in the Louisiana Purchase.
Initially nothing happened very much. After the discovery of gold in the region in 1852 however, east and west were united in 1863 and came to belong to Idaho for a year.Montana was designated as a United States territory (Montana Territory) on 26 May 1864 which was organized from the existing Idaho Territory by Act of Congress and signed into law by President Abraham Lincoln on 28 May 28, 1864. As the State of Montana, it was admitted to the Union as its 41st state on 26 May 1889.
The Great Seal of the Territory of Montana evolved from a basic design submitted by Francis McGee Thompson, a representative from Beaverhead County at the First Legislative Assembly at Bannack, the Territorial capital, during the winter of 1864-65.
sketch of the proposed seal for the Territory of Montana
made by Francis M. Thompson, member of the committee on the seal in the first legislative assembly
MHS Archives collection SC 839 
Thompson's design contained the words "Oro el Plata,", two of the riches that gave rise to the nickname Treasure State. This was changed to read "Oro y Plata," Spanish for gold and silver. Indeed, it is interesting to note that during the first Territorial legislative deliberations on this subject, consideration was given to using the word "Eldorado" instead of "Oro y Plata." This proposal of was voted down.
The seal also features a plow and a miner's pick and shovel above these words to illustrate the state's agricultural and mineral wealth. These are surrounded by the mountains for which Montana was named, as well as by the Great Falls of the Missouri River, which so dazzled explorers Lewis and Clark.
The Territorial resolution accepting Thompson's design was passed on 9 February 1865, and signed the same day by Territorial Governor Sidney Edgerton. The resolution read:
"The Territorial seal shall as a central group represent a plow, a miners pick and shovel, upon the left mountain scenery, underneath as a motto the words Oro el Plata. The seal shall be two inches in diameter and surrounded by these words, The Seal of the Territory of Montana."
The original designers of the seal were members of a legislative committee chaired by Francis M. Thompson, in the days when Montana was still a territory. Thompson was not without some expertise: he had engraved seals for Montana's first mining districts on the ends of ax handles. The committee wanted to incorporate into the design the essential elements of Montana's economy and its natural attributes. The first seal included bison and other animals, but these were removed by later designers who thought the seal was too cluttered. Thompson, who came to the Territory from Massachusetts in 1862, returned to his home state in 1865. His original hand drawn design for the seal is preserved in the Historical Society of Montana.
When Montana changed from a territory to a state in 1889, the seal changed, too. In 1891, shortly after Montana became a state, legislators debated the design of the seal at length and suggested adding Indians, settlers, miners, horses, sheep, cattle -- even a train or stagecoach. Recognizing that the seal could quickly become overpopulated, the lawmakers finally decided to leave well enough alone. Montana's first seal had a buffalo where the trees are now, and the falls and river were different, but it was very close to the original. They satisfied themselves with changing the word "Territory" to "State."
The Territorial seal was used until the Third Legislative Assembly that the basic design received sanction as The Great Seal of the State of Montana. The adopting resolution was passed March 2, 1893. The act reads:
“Be it enacted by the Legislative Assembly of the State of Montana:
SECTION I There shall be
a great Seal of the State of Montana, which shall be of the following design,
namely: A central group representing a plow, a miner’s pick and shovel; upon
the right a representation of the great falls of the Missouri River; upon the
left mountain scenery, and underneath, the words ‘ORO-Y-PLATA.’ the seal must be two and one-half inches in diameter, and surrounded
by these words, THE GREAT
SEAL OF THE STATE OF MONTANA.’
SECTION 2 All Acts and parts of Acts in conflict with
this Act are hereby repealed.
SECTION 3 This Act shall take effect and be in force
from and after passage.
Two years later the man who made the drawings for the State seal, based on the original Territorial design was paid $20 for his work. House Bill 178, approved March 2, 1895, directed: "That the sum of twenty dollars be, and the same is hereby appropriated out of any moneys in the State Treasury not otherwise appropriated, for the relief of G.R. Metten for services rendered the State in the year 1893, drawing designs for the Great Seal of Montana."
By law, the Secretary of State is charged with keeping the State Seal, and is the only one who has the authority to affix it to public documents, including those signed by the governor. 
Arrival of Captain Lewis at the Great Falls of the Missouri, 13 June 1805 
Painting by Charles Fritz
Oil on Canvas 106 ´ 165 cm
emblem, 1876 design 
A quasi coat of arms for the Territory and the State of Montana was designed some years after the civil war but was never approved nor adopted officially. It showed the landscape of the seal of 1865 in full color with the motto underneath. Representations date from 1876.
Æ See illustration in the head of this article. 
That for the regiments and separate battalions of the Montana Army National Guard: From a wreath of colors, a fleur-de-lis the middle leaf and tie Or, and outside leaves Argent.
Montana was one of the last states carved from the Louisiana Purchase. The seal of the State bears the motto "ORO Y PLATA" (gold and silver). The gold and silver fleur-de-lis is significant of the State having been a part of the Louisiana Purchase.
The crest for color bearing organizations of the State of
Montana was approved on 4 January 1924.
Shoulder Sleeve Insignia
On a yellow disc 6.35 cm in diameter, eight orange rays behind a blue snow-capped mountain peak, all inset 3,2 mm.
The shoulder sleeve insignia was originally approved for Headquarters
and Headquarters Detachment, Montana National Guard on 27 May 1952. It
was redesignated for all nondivisional units of the
Montana National Guard on 2 September 1955. The insignia was
redesignated on 30 December 1983, for Headquarters,
State Area Command, Montana Army National Guard. (TIOH Dwg. No.
Distinctive Unit Insignia
A gold color metal and enamel device 1 1/8 inches (2.86 cm) in width overall consisting of a fleur-de-lis with a yellow middle leaf and tie and two white outer leaves, within and between the angle formed by two conjoined gold chevrons each enclosing a triangular blue background with a white apex.
The fleur-de-lis, an adaptation from the crest of Montana Army National Guard, symbolizes the geographical apportionment of the last of the states carved from the Louisiana Purchase. The colors yellow and white (gold and silver) of the fleur-de-lis refer to the inscription "ORO Y PLATA" from the State Seal and together with the gold chevrons further symbolize the rich gold deposits within the "Bonanza State." The simulated mountain peaks allude to "Montana," a Spanish word for mountain.
The distinctive unit insignia was originally approved for Headquarters and Headquarters Detachment and noncolor bearing units of the Montana Army National Guard on 11 June 1971. The insignia was redesignated effective 30 December 1983, for Headquarters, State Area Command, Montana Army NationalGuard.
Assiniboine and Sioux Tribes of the
Fort Peck Indian Reservation
Blackfeet Tribe of the Blackfeet Indian
Chippewa-Cree Indians of the Rocky
Confederated Salish & Kootenai Tribes
of the Flathead Reservation,
Coat of arms
On a red cloth with the
inscription ‘Flathead Nation’
Crow Tribe of Montana
Fort Belknap Indian Community of the
Fort Belknap Reservation
Little Shell Tribe of Chippewa Indians
The Little Shell Chippewa Tribe is without a reservation or
land base and members live in various parts of Montana.
Northern Cheyenne Tribe of the Northern
Cheyenne Indian Reservation,
Turtle Mountain Band of Chippewa
Indians of Montana, North Dakota and South Dakota
© Hubert de Vries 2017-07-11
 Zieber, Eugene: Heraldry in America. Published by the Department of Heraldry of the Bailey, Banks and Biddle Company. Philadelphia, Pennsylvania, 1895. P. 149. Also:: Laws of Montana, Third Session, 1893: Laws, Resolutions and Memorials of the State of Montana Passed at the third Regular Session of the Legislative Assembly, Held at Helena, the Seat of Government of Said State, Commencing January 2nd, 1893, and ending March 2nd, 1893, published by authority (Inter Mountain Publishin Company, State Printers, Butte City, Montana, 1893) p. 42.3.
 Meriweather Lewis, (†1809), 2nd Governor of (American) Louisiana.
A.J.: Arms of the States and Territories of the American Union. Washington D.C.
 Mitchell, Henry: The State Arms of the
Union, Boston: L. Prang & Co. 1876