“[I]f ever there was a holy war, it was that which saved our liberties and gave us independence.”

Speech to Conservative Party Conference (12 October 1990) http://www.margaretthatcher.org/document/108217
Third term as Prime Minister
Context: The toppling of the Berlin Wall. The overthrow of Ceausescu by the people he had so brutally oppressed. The first free elections in Eastern Europe for a generation. The spread of the ideas of market freedom and independence to the very heart of the Soviet Leviathan... Our friends from Eastern Europe reminded us that no force of arms, no walls, no barbed wire can for ever suppress the longing of the human heart for liberty and independence. Their courage found allies. Their victory came about because for forty long, cold years the West stood firm against the military threat from the East. Free enterprise overwhelmed Socialism. This Government stood firm against all those voices raised at home in favour of appeasement. We were criticised for intransigence. Tempted repeatedly with soft options. And reviled for standing firm against Soviet military threats. When will they learn? When will they ever learn?

1962, Address at Independence Hall

This is also sometimes quoted as "The millions of people, armed in the holy cause of liberty".
1770s, "Give me liberty, or give me death!" (1775)
Context: They tell us, sir, that we are weak; unable to cope with so formidable an adversary. But when shall we be stronger? Will it be the next week, or the next year? Will it be when we are totally disarmed, and when a British guard shall be stationed in every house? Shall we gather strength by irresolution and inaction? Shall we acquire the means of effectual resistance by lying supinely on our backs and hugging the delusive phantom of hope, until our enemies shall have bound us hand and foot?
Sir, we are not weak if we make a proper use of those means which the God of nature hath placed in our power. Three millions of people, armed in the holy cause of Liberty, and in such a country as that which we possess, are invincible by any force which our enemy can send against us. Besides, sir, we shall not fight our battles alone. There is a just God who presides over the destinies of nations, and who will raise up friends to fight our battles for us. The battle, sir, is not to the strong alone; it is to the vigilant, the active, the brave.

The Need for Transcendence in the Postmodern World (1994)

America, reported in Bartlett's Familiar Quotations, 10th ed. (1919).

Speech at Edwardsville, Illinois (11 September 1858); quoted in Lincoln, Abraham; Mario Matthew Cuomo, Harold Holzer, G. S. Boritt, Lincoln on Democracy http://books.google.de/books?id=8bWmmyJEMZoC&pg=PA128 (Fordham University Press, September 1, 2004), 128. .
Variant of the above quote: What constitutes the bulwark of our own liberty and independence? It is not our frowning battlements, our bristling sea coasts, our army and our navy. These are not our reliance against tyranny All of those may be turned against us without making us weaker for the struggle. Our reliance is in the love of liberty which God has planted in us. Our defense is in the spirit which prizes liberty as the heritage of all men, in all lands everywhere. Destroy this spirit and you have planted the seeds of despotism at your own doors. Familiarize yourselves with the chains of bondage and you prepare your own limbs to wear them. Accustomed to trample on the rights of others, you have lost the genius of your own independence and become the fit subjects of the first cunning tyrant who rises among you.
Fragment of Speech at Edwardsville, Ill., September 13, 1858; quoted in Lincoln, Abraham; The Writings of Abraham Lincoln V05 http://www.classic-literature.co.uk/american-authors/19th-century/abraham-lincoln/the-writings-of-abraham-lincoln-05/ebook-page-05.asp) p. 6-7
1850s
Context: What constitutes the bulwark of our own liberty and independence? It is not our frowning battlements, our bristling sea coasts, the guns of our war steamers, or the strength our gallant and disciplined army? These are not our reliance against a resumption of tyranny in our fair land. All of those may be turned against our liberties, without making us weaker or stronger for the struggle. Our reliance is in the love of liberty which God has planted in our bosoms. Our defense is in the preservation of the spirit which prizes liberty as the heritage of all men, in all lands, everywhere. Destroy this spirit, and you have planted the seeds of despotism around your own doors. Familiarize yourselves with the chains of bondage and you are preparing your own limbs to wear them. Accustomed to trample on the rights of those around you, you have lost the genius of your own independence, and become the fit subjects of the first cunning tyrant who rises.

A toast made by Grant before his operations in the Vicksburg Campaign, (22 February 1863); as quoted in A Popular and Authentic Life of Ulysses S. Grant (1868) by Edward Deering Mansfield
1860s

Views on civil rights declared in a written statement requested by Robert W. Kenny, read during fund raising luncheon at the Biltmore Hotel, in Los Angeles, in the summer of 1938, quoted in Lawyers Guild Review Vol. 13-14 (1953), p. 47; he mentions Frank Hague, who had declared earlier in the year:
Context: I believe the preservation of our civil liberties to be the most fundamental and important of all our governmental problems, because it always has been with us and always will be with us and if we ever permit those liberties to be destroyed, there will be nothing left in our system worthy of preservation. They constitute the soul of democracy. I believe that there is grave danger in this country of losing our civil liberties as they have been lost in other countries. There are things transpiring in this country today that are definitely menacing our future; among which are the activities of Mayor Hague and other little Hagues throughout the country. These activities are so basically wrong and so menacing to our institutions that every citizen and particularly every public official should oppose them to the limit of their strength.

1940s
Source: Said to General Heinz Guderian, 4 August 1941, as quoted Panzer Leader (1952) by Heinz Guderian