Loyalty is a devotion to a country, philosophy, group, or person. Philosophers disagree on what can be an object of loyalty, as some argue that loyalty is strictly interpersonal and only another human being can be the object of loyalty. The definition of loyalty in law and political science is the fidelity of an individual to a nation, either one's nation of birth, or one's declared home nation by oath (naturalization).
Classical tragedy is often based on a conflict arising from dual loyalty.
Euthyphro, one of Plato's early dialogues, is based on the ethical dilemma arising from Euthyphro intending to lay manslaughter charges against his own father, who had caused the death of a slave through negligence.
In the Gospel of Matthew , Jesus states, "No one can serve two masters; for a slave will either hate the one and love the other, or be devoted to the one and despise the other. You cannot serve God and wealth". This relates to the authority of a master over his servants (as per Ephesians ), who, according to Biblical law, owe undivided loyalty to their master (as per ).
On the other hand, the "Render unto Caesar" of the synoptic gospels acknowledges the possibility of distinct loyalties (secular and religious) without conflict, but if loyalty to man conflicts with loyalty to God, the latter takes precedence.
The Encyclopædia Britannica Eleventh Edition defines loyalty as "allegiance to the sovereign or established government of one's country" and also "personal devotion and reverence to the sovereign and royal family". It traces the word "loyalty" to the 15th century, noting that then it primarily referred to fidelity in service, in love, or to an oath that one has made. The meaning that the Britannica gives as primary, it attributes to a shift during the 16th century, noting that the origin of the word is in the Old French loialte, that is in turn rooted in the Latin lex, meaning "law". One who is loyal, in the feudal sense of fealty, is one who is lawful (as opposed to an outlaw), who has full legal rights as a consequence of faithful allegiance to a feudal lord.