Embassy (and Ambassador) and its Spanish equivalent, Embajada (and Embajador), both come from the same ancestor, the Old French Ambactos.
What is most interesting about these two is that it is an example of the pattern where the ‑j- sound in Spanish maps to the ‑sh- sound (and its cousins, like ‑ss- and ‑ch-) in English. Remember syrup and jarabe, chess and ajedrez, sherry and jerez, and push and empujar for a few examples.
Thus, the m‑b-j of emabajada maps to the m‑b-ss of embassy.
Allegiance is a very Roman idea: strong loyalty to your team, your empire.
So it’s not surprising that the word itself comes from the Latin, ligare — to bind. Your allegiance is what binds you or ties you to your team.
From the Latin ligare, we get the Spanish… ligar, meaning the same, tying or binding!
Thus, the l‑g root is clearly visible in both versions.
The Spanish “Huir” comes from the same Latin root as “fugitive”, “fugitivus”, meaning, “to flee”.
Pattern: Latin words that began with an ‘F’ tended to lose that initial ‘F’ sound and became silent (yet represented in writing with an ‘H’) as vulgar Latin turned into Spanish.
Salir, the common Spanish word meaning, “to leave” sounds like it has nothing to do with anything. Or does it?
Salir comes from the Latin salire meaning the same, “to jump”. Surprise, surprise.
From this same Latin root was get a bunch of fun English words, including:
We also get another Spanish word from the same root: saltar (“to jump”). You can see the s‑l mapping across all descendants of the word!
Lazar (Spanish for “to tie, such as with a ribbon”) comes from the Latin laqueum, meaning “a tie, such as a noose”. From that same root, we get the English… lasso. A lasso, after all, is really a cable that can be used to tie someone or something up…!
The l‑z of lazar clearly maps to the l‑ss of lasso.