John of Salisbury in the 1100s in Policraticus:
While recognizing a prince's supreme temporal power, Salisbury argued that princes must be subordinate to the will of God and the Church.
"For myself, I am satisfied and persuaded that loyal shoulders should uphold the power of the ruler; and not only do I submit to his power patiently, but with pleasure, so long as it is exercised in subjection to God and follows His ordinances. But on the other hand if it resists and opposes the divine commandments, and wishes to make me share in its war against God; then with unrestrained voice I answer back that God must be preferred before any man on earth. Therefore inferiors should cleave and cohere to their superiors, and all the limbs should be in subjection to the head; but always and only on condition that religion is kept inviolate."
In Salisbury's mind, a tyrant sets a poor example for his people and could lead them from God. His example was the Roman Emperor Julian the Apostate, who attempted to restore Rome's pagan religion. In this case, Salisbury argued that killing a regent, when all other resources were exhausted, was not only justifiable but necessary, and he called a tyrant an "image of depravity . . . [who] spring(s) from evil and should be cut down with the axe wherever he grows." This may be the first defense of tyrannicide to be written after Antiquity.
Perhaps due to my classical liberal or libertarian biases, I don't understand why they advocate for killing tyrants over simply declaring them as no longer king and acting as such, using whatever physical force to escort them off properties for trespassing if necessary, or even imprisoning such people. Salisbury said that such should be done "when all other resources were exhausted" - so perhaps this idea is an idea of complete last resort, maybe in a chaotic time of war or something. Or perhaps this was some of the bias of the medieval era which started to think that punishing heresy forcibly was a good thing. Perhaps they did advocate for using all other such means first.
Various Christian philosophers and theologians also wrote about tyrannicide. In Thomas Aquinas's commentary on the Sentences of Peter Lombard, Aquinas gave a defense not only of disobedience to an unjust authority, using as an example Christian martyrs in the Roman Empire, but also of "one who liberates his country by killing a tyrant."[8] The Monarchomachs in particular developed a theory of tyrannicide, with Juan de Mariana describing their views in the 1598 work De rege et regis institutione,[9] in which he wrote, "[B]oth the philosophers and theologians agree, that the prince who seizes the state with force and arms, and with no legal right, no public, civic approval, may be killed by anyone and deprived of his life..."[5]
So perhaps they have in mind some kind of revolutionary who seizes power?
Thomas Aquinas also wrote of the right to resist tyrannical rule in the Summa Theologica. John of Salisbury advocated direct revolutionary assassination of unethical tyrannical rulers in his Policraticus. This theological notion was expanded in the Early Modern Period. The Jesuits, especially Robert Bellarmine and Juan de Mariana, were widely known and often feared for advocating resistance to tyranny and often tyrannicide—one of the implications of the natural law focus of the School of Salamanca.
Thomas Aquinas condoned extra-legal tyrannicide in the worst of circumstances:
When there is no recourse to a superior by whom judgment can be made about an invader, then he who slays a tyrant to liberate his fatherland is [to be] praised and receives a reward.
— Commentary on the Magister Sententiarum[4]
On the other hand, Aquinas forbade the overthrow of any morally, Christianly and spiritually legitimate king by his subjects. The only human power capable of deposing the king was the pope. The reasoning was that if a subject may overthrow his superior for some bad law, who was to be the judge of whether the law was bad? If the subject could so judge his own superior, then all lawful superior authority could lawfully be overthrown by the arbitrary judgement of an inferior, and thus all law was under constant threat. Towards the end of the Middle Ages, many philosophers, such as Nicholas of Cusa and Francisco Suarez, propounded similar theories.
I guess it would be a kind of self-defense in circumstances that threatened the survival of the society.
Otherwise, obedience to secular authorities, provided they aren't commanding people to sin, is often promoted.
The example of Jesus seemed to be one of overcoming tyrannical circumstances by peacefully enduring unjust actions, rather than seeking to violently overthrow them.
What is to be thought of some of these theories of tyrannicide?
Self defense, of oneself or of one’s family or other dependents, can be a moral duty, and therefore good and a necessity.
A more recent example to add to your list would be the German soldiers who secretly sought church advice on morality of killing Hitler. Encouraged to proceed as a last resort, a bomb was placed, which was however not successful.