All 7 Uses of

alliance
in
The Magic Mountain

For whereas Lodovico, as he himself reported with bitterness, found himself restricted to deriding life and manners at the International Sanatorium Berghof, to offering his sardonic criticism and protesting in the name of beautiful, vigorous humanity, his grandfather had given governments trouble, had conspired against Austria and the Holy Alliance, which in those days held his dismembered fatherland in the grip of darkest bondage, and had been a zealous member of certain secret societies that had spread throughout Italy—a Carbonaro, as Settembrini suddenly declared, lowering his voice, as if it were still dangerous even now to speak the word.†
Chpt 4.9

alliance = association formed to support common interests

But that day would come, Settembrini said, smiling delicately beneath his moustache—it would come, if not on the feet of doves, then on the pinions of eagles, and would burst as the dawn of universal brotherhood under the emblem of reason, science, and justice; it would bring about a new Holy Alliance of bourgeois democracies, the shining antithesis of that thrice-infamous alliance of princes and ministers whom Grandfather Giuseppe had declared his personal enemies—in a word, the Republic of the World.†
Chpt 4.9

But that day would come, Settembrini said, smiling delicately beneath his moustache—it would come, if not on the feet of doves, then on the pinions of eagles, and would burst as the dawn of universal brotherhood under the emblem of reason, science, and justice; it would bring about a new Holy Alliance of bourgeois democracies, the shining antithesis of that thrice-infamous alliance of princes and ministers whom Grandfather Giuseppe had declared his personal enemies—in a word, the Republic of the World.†
Chpt 4.9

But when he saw the calm, uncomprehending smile with which his nephew responded to his jokes, the way it perfectly mirrored this whole community's intact self-assurance, he took alarm; and fearing the loss of his business energies, he quickly concluded that he would have that decisive conversation with the director about his nephew at once—that very afternoon if at all possible—while he still had a spirit of his own and energies from the world below with which to attack, for he could feel those energies vanishing and the spirit of the place joining forces with his own good breeding in a dangerous alliance against them.†
Chpt 6.5

Shall we build a friendship, establish an alliance for someone, instead of against someone as is usual?†
Chpt 7.4 *

Admittedly, however, Kotzebue had been in the employ of the Russians, that is, of the Holy Alliance; and so Sand was presumably striking a blow for freedom—but that, too, turned improbable when one considered the fact that he counted Jesuits among his closest friends.†
Chpt 7.9

uniting for universal happiness, there would come a sound as of the rushing pinions of eagles—not that he wished it or even knew whence it came, though doubtless it originated in the politics he had inherited from his grandfather, which had then blended with the humanistic inheritance of his father to create beautiful literature within him, Lodovico, just as humanity and politics were blended in the lofty idea of civilization, to which he raised a toast, an idea full of the mildness of the dove and the boldness of the eagle and awaiting its day, the dawn of the Day of Nations, when the principle of obduracy would be defeated and a path opened for the Holy Alliance of bourgeois democracy.†
Chpt 7.10

Definition:

an association formed to support common interests