Quamvis epulae simplices sint, convivium tamen omnibus gratum est.

Because quamvis is commonly followed by the subjunctive when it means although / even though.

So in:

Quamvis epulae simplices sint

the clause is a concessive clause: although the dishes are simple.

A learner might expect sunt because the statement is factual, but after quamvis, Latin regularly uses the subjunctive by rule, not necessarily because the idea is doubtful or unreal.

So:

• sunt = they are
• sint = they may be / are, in a subjunctive clause

Here, English usually just translates it with a normal indicative: although the dishes are simple.

Here quamvis means although or however much.

In this sentence, it introduces a contrast:

• Quamvis epulae simplices sint = Although the dishes are simple
• convivium tamen omnibus gratum est = the banquet is still pleasing to everyone

So quamvis sets up the concession, and the main clause gives the result that still holds true despite that concession.

Yes, quamvis already signals concession, but Latin often likes to reinforce the contrast with tamen, meaning nevertheless / still / yet.

So the pattern is:

• quamvis = although
• tamen = nevertheless / still

Together they make the contrast very clear:

Although the dishes are simple, nevertheless the banquet is pleasing to everyone.

In natural English, we often leave out nevertheless, but in Latin it is very common to include tamen in the main clause.

Because epulae is normally a plural noun in Latin.

It often refers to:

• a feast
• food
• courses / dishes of a meal

Even when English might use a singular word like food or feast, Latin often uses the plural epulae.

That is why the words agreeing with it are plural too:

• epulae = nominative plural
• simplices = nominative plural
• sint = plural verb

So the grammar is fully consistent.

Because simplices agrees with epulae.

Epulae is:

• feminine
• nominative
• plural

So the adjective describing it must also be nominative plural feminine. For this adjective, that form is simplices.

So:

• epulae simplices = simple dishes or simple fare

This is a good example of adjective agreement in Latin: adjectives match the nouns they describe in gender, number, and case.

Because they are not the same word and do not mean exactly the same thing.

• epulae refers to the food / dishes / feast fare
• convivium refers to the banquet / dinner party / social gathering

So the sentence contrasts the simplicity of the food with the pleasantness of the event as a whole.

That is why Latin can say:

• epulae = plural
• convivium = singular

In other words, the dishes may be simple, but the banquet itself is pleasing to everyone.

Omnibus is dative plural.

It comes from omnis, omne and here means to everyone or for everyone.

It is used because gratus often takes the dative of the person who feels pleasure or approval.

So:

• convivium ... gratum est omnibus
• literally: the banquet is pleasing to everyone
• more word-for-word: the banquet is agreeable to everyone

This is a very common Latin pattern:

• alicui gratus est = is pleasing to someone

Latin often expresses to be pleasing with the adjective gratus plus esse.

So instead of using a single verb equivalent to English please, Latin says:

• gratus, grata, gratum = pleasing, welcome
• est = is

Therefore:

• gratum est = is pleasing / is welcome

Since convivium is:

• nominative
• singular
• neuter

the adjective must agree with it, so we get gratum.

This is another agreement pattern:

• convivium → neuter singular
• gratum → neuter singular

The sentence has two parts:

1. Quamvis epulae simplices sint

   • concessive subordinate clause
   • Although the dishes are simple

2. convivium tamen omnibus gratum est

   • main clause
   • the banquet is nevertheless pleasing to everyone

So the overall structure is:

Although X, nevertheless Y.

That makes it a very useful model sentence for learning how Latin expresses contrast.

Not especially, but it is characteristically Latin.

A more mechanically rearranged version would be:

Quamvis epulae simplices sint, tamen convivium est omnibus gratum.

But Latin is flexible with word order, and the given version is natural.

A few things to notice:

• quamvis starts the subordinate clause
• tamen appears early in the main clause, which is common
• omnibus gratum est keeps the adjective and verb together nicely
• gratum est comes at the end, giving a neat close to the sentence

Latin word order often reflects emphasis and style more than strict grammatical necessity, because the endings already show the relationships between the words.

Yes, but the construction would usually be different.

• quamvis commonly takes the subjunctive
• quamquam more often takes the indicative

So you could compare:

• Quamvis epulae simplices sint = Although the dishes are simple
• Quamquam epulae simplices sunt = Although the dishes are simple

Both can translate similarly in English, but the grammar differs. In your sentence, quamvis ... sint is the expected pairing.

Yes. Latin is drawing a subtle distinction.

• epulae focuses on the meal itself, especially the food served
• convivium focuses on the shared social event, the banquet or dinner gathering

So the idea is something like:

Even if the food is plain, the occasion itself is enjoyable and appreciated by everyone.

That distinction helps explain why the sentence feels elegant: it is not just repeating the same idea twice, but contrasting simple fare with a pleasant gathering.