The notion of all secessionist efforts succeeding isn't really coherent because one movement would impact others and the levels of seriousness of some of the efforts vary greatly.
But, some useful background data is here:
Quebec in Canada, has made secessionist bids (and failed). There have also been discussions at times about the maritime provinces of Canada forming a separate dominion.
Nunavut which was part of the Northwest Territories in Canada until 1999 received a semi-sovereign status as the equivalent of an Indian Reservation in the U.S.
The Pacific Northwest, called the Oregon Territory was ceded from the U.K. to the U.S. in the Treaty of 1818.
The Northern part of the Oregon territory was ceded back to the U.K. in 1846.
Keep in mind that until the Louisiana Purchase in 1803, most of the Mississippi River basin was under French Sovereignty.
Until 1870, much of Canada was part of the U.K. and not Canada (Oregon Territory, all of which was once part of the U.S., included essentially all of what is shown as "British Columbia" on the map below).
The state of Chiapas in Mexico, sometimes with the state of Oaxaca in Mexico has has insurgencies seeking indigenous people's rights. Part of Chiapas was once part of the Federal Republic of Central America (which existed in some form or another from 1821-1841).
The republic consisted of the present-day states of Guatemala, El
Salvador, Honduras, Nicaragua, and Costa Rica. (Panama was part of
Bolivar's República de Colombia in 1821, Belize later became a British
colony in 1862.) In the 1830s, an additional sixth state was added –
Los Altos, with its capital in Quetzaltenango – occupying parts of
what are now the western highlands of Guatemala and Chiapas state in
southern Mexico. Maps and borders hardly existed at the time so
locations are only approximate.
Obviously, there were the Confederate States of America including Texas which was an independent Republic for a while (with somewhat different borders). Also, parts of Kentucky and Missouri attempted to secede but failed, and West Virginia rejoined the union after Virginia's secession.
Texas, New Mexico, Arizona, Nevada, parts of Colorado and California and much of the territory in between was part of Mexico until in was acquired by conquest in the Mexican-American War (most of the action took place from 1846-1848). Prior to the Mexican-American War the boundaries of the region looked like this:
Early on in the Mexican American War, Anglo settlers in the Mexican State of Alta California briefly attempted to form the Bear Republic, which might have persisted if annexation to the U.S. had not followed:
A separate New England confederation was seriously discussed in the early 1800s and might have included some of the Maritime provinces of Canada.
Alaska was part of Russia until it was purchased by the U.S. in 1867.
Hawaii (f.k.a. the Sandwich Islands) doesn't necessarily have a secessionist movement, but it was an independent kingdom and there are efforts underway to give native Hawaiians recognized under a trust created by the former king legal status as an Indian tribe.
The legal term for territory in the United States subject to Native American tribal sovereignty is Indian Country.
Puerto Rico has had an independence movement ever since it became a U.S. territory following the Spanish-American War in 1898 which also brought exterior possessions such as the Philippines to the U.S. that were later ceded.
Florida was ruled by Spain from 1513–1763, then by the British from 1763–1783, and then by Spain again from 1783–1821, after which it became a U.S. territory and then state until 1861 when it joined the Confederate States of America until it was forcefully returned to the United States in 1865.
A State of Deseret was proposed in 1849 and likely would have sought to secede if successfully formed. There was a short insurgency in Utah from 1857-1858 called the Utah War.
To quote a Wikipedia summary of recent secessionist efforts (citations omitted):
Alaska: In November 2006, the Alaska Supreme Court held in the case [Kohlhaas v. State] that secession was illegal, and refused to
permit an initiative to be presented to the people of Alaska for a
vote. The Alaskan Independence Party remains a factor in state
politics.
California: This was discussed by involved grassroots movement parties and small activist groups calling for the state to secede from
the union, they met in a pro-secessionist meeting in Sacramento on
April 15, 2010 to discuss advancing the matter. In 2015, a Political
Action Committee called the "Yes California Independence Committee"
formed to advocate California's independence from the United States.
On January 8, 2016, the California Secretary of State's office
confirmed that a political body called the California National Party
filed the appropriate paperwork to begin qualifying as a political
party. The California National Party, whose primary objective is
California independence, is running a candidate for State Assembly in
the June 7, 2016 primary.
Florida: The mock 1982 secessionist protest by the Conch Republic in the Florida Keys resulted in an ongoing source of
local pride and tourist amusement. In 2015, right-wing activist Jason
Patrick Sager called for Florida to secede.
Georgia: On April 1, 2009, the Georgia State Senate passed a resolution, 43–1, that asserted the right of states to nullify federal
laws under some circumstances. The resolution also asserted that if
Congress, the president, or the federal judiciary took certain steps,
such as establishing martial law without state consent, requiring some
types of involuntary servitude, taking any action regarding religion
or restricting freedom of political speech, or establishing further
prohibitions of types or quantities of firearms or ammunition, the
constitution establishing the United States government would be
considered nullified and the union would be dissolved.
Hawaii: The Hawaiian sovereignty movement has a number of active groups that have won some concessions from the state of Hawaii,
including the offering of H.R. 258 in March 2011, which removes the
words "Treaty of Annexation" from a statute. It has passed a committee
recommendation 6-0 thus far.
With the decision of the Supreme Court of the United States to hear
District of Columbia v. Heller in late 2007, an early 2008 movement
began in Montana involving at least 60 elected officials
addressing potential secession if the Second Amendment were
interpreted not to grant an individual right, citing its compact with
the United States of America.
New Hampshire: On September 1, 2012 "The New Hampshire Liberty Party was formed to promote independence from the federal government
and for the individual." The Free State Project is another NH based
movement that has considered secession to increase liberty. On July
23, 2001 founder of the FSP, Jason Sorens, published "Announcement:
The Free State Project", in The Libertarian Enterprise stating, "Even
if we don't actually secede, we can force the federal government to
compromise with us and grant us substantial liberties. Scotland and
Quebec have both used the threat of secession to get large subsidies
and concessions from their respective national governments. We could
use our leverage for liberty."
South Carolina: In May 2010 a group formed that called itself the Third Palmetto Republic, a reference to the fact that the state
claimed to be an independent republic twice before: once in 1776 and
again in 1860. The group models itself after the Second Vermont
Republic, and says its aims are for a free and independent South
Carolina, and to abstain from any further federations.
Texas Secession Movement: The group Republic of Texas generated national publicity for its controversial actions in the late 1990s. A
small group still meets. In April 2009, Rick Perry, the Governor of
Texas, raised the issue of secession in disputed comments during a
speech at a Tea Party protest saying "Texas is a unique place. When we
came into the union in 1845, one of the issues was that we would be
able to leave if we decided to do that...My hope is that America and
Washington in particular pays attention. We've got a great union.
There's absolutely no reason to dissolve it. But if Washington
continues to thumb their nose at the American people, who knows what
may come of that."
Vermont: The Second Vermont Republic, founded in 2003, is a loose network of several groups that describes itself as "a nonviolent
citizens' network and think tank opposed to the tyranny of Corporate
America and the U.S. government, and committed to the peaceful return
of Vermont to its status as an independent republic and more broadly
the dissolution of the Union." Its "primary objective is to extricate
Vermont peacefully from the United States as soon as possible."[100]
They have worked closely with the Middlebury Institute created from a
meeting sponsored in Vermont in 2004. On October 28, 2005, activists
held the Vermont Independence Conference, "the first statewide
convention on secession in the United States since North Carolina
voted to secede from the Union on May 20, 1861". They also
participated in the 2006 and 2007 Middlebury-organized national
secessionist meetings that brought delegates from over a dozen groups.
Republic of Lakotah: Some members of the Lakota people of Montana, Wyoming, Nebraska, North Dakota, and South Dakota created the Republic
to assert the independence of a nation that was always sovereign and
did not willingly join the United States; therefore they do not
consider themselves technically to be secessionists.
Pacific Northwest: Cascadia: There have been repeated attempts to form a Bioregional Democracy Cascadia in the northwest. The core of
Cascadia would be made up through the secession of the states of
Washington, Oregon and the Canadian province of British Columbia,
while some supporters of the movement support portions of Northern
California, Southern Alaska, Idaho and Montana joining, to define its
boundaries along ecological, cultural, economic and political
boundaries.
Northwest Front: The Northwest Front is a white separatist movement that is advocating for the formation of an independent
sovereign republic in the Pacific Northwestern states of Washington,
Oregon, Idaho and western Montana, that will serve as a "white
homeland" for white people throughout the world. The nationalist
movement is led by Harold Covington. League of the South: The group
seeks "a free and independent Southern republic" made up of the former
Confederate States of America. It operated a short-lived Southern
Party supporting the right of states to secede from the Union or to
legally nullify federal laws.
