In my great-great-grandfather’s biography, I found rules adopted by the High Council of the Juarez Stake of Zion (and Mexico) for “parties of the Latter-day Saints” in 1897. There are only 5:

Rules

No.1. All parties should be opened and closed by prayer and commence at 7:30 P.M. and close not later than midnight.

No. 2. All persons not in possession of proper recommendation as to their standing in the Church of Jesus Christ of Latter-day Saints shall be excluded from dancing in any of our parties. (Non-members might be admitted provided the Bishopric or a majority of the members of the Bishopric shall see a necessity for it).

No. 3. That we do not participate in round dancing, swinging around the waist, improper or excessive swinging of any kind.

No. 4. That there be no liquor, tobacco nor bad language used in nor around the buildings when parties are held and that no person under the influence of liquor be allowed inside the building.

No. 5. That any person not willing to sustain the above rules nor maintain a gentlemanly or ladylike conduct during parties shall be excluded.

Here are the current equivalent from my stake (I believe they are fairly typical)

Dress and appearance should be modest, tasteful and appropriate for the activity. Tight fitting and revealing clothes are not appropriate. Underclothing should be covered at all times. Extremes in clothing, appearance and hairstyle should be avoided.
Dress Standards for activities designated “Sunday Dress”: Men: Dress slacks, dress shirt, tie, socks and shoes.
• No jeans or hats. Women: Dress or skirt and blouse and shoes.
• Dresses and skirts of appropriate length – coming down to at least the middle of the knee and any slits should not go above the middle of the knee.
• Modest blouses that cover the shoulder and midriff (when arms are raised). No sleeveless, low cut, sheer or tight fitting blouses, tops or dresses.
• No slacks, jeans or baseball caps.
Dress Standards for activities designated “Casual Dress”: Men: Clean modest shirt and slacks or shorts.
• Shorts must be to the knee or below.

• No tanktops, offensive tee shirts or bare midriffs.

• No baseball caps when in Church building.
Women: Clean modest shirt or blouse and slacks or shorts.

• Shirts/blouses should cover the shoulder and midriff (when arms are raised).
No sleeveless, low cut, sheer or tight fitting blouses or tops.

• No tanktops or offensive tee shirts.

• Shorts must be to the knee or below.

• No baseball caps when in Church building.
When dancing, avoid full body contact with your partner. Do not use positions or moves that are suggestive of sexual behavior.
Music should not: drive away the Spirit, encourage immorality, glorify violence, use foul or offensive language, or promote Satanism or other evil practices.
Building Rules:
• Youth are not allowed in classrooms or the Chapel (unless being used for the activity).

• Youth are not to leave the activity without permission.

• Youth must let chaperones know where they are at all times.

• Respect the building and its contents.
Other:
• Respect other people’s property.

• Use appropriate language.

• Treat others with respect.

My stake does not currently use a dance card; we encourage all kids to come, as long as they conform to our expectations in behavior.

The obvious disparity is dress code: we are OBSESSED with it, aren’t we? I suspect, however, that some of that can be chalked up to audience: I believe that the Juarez stake party guidelines were for adults as well as youth, and our guidelines are specifically targeted at youth. I don’t know how offensive “round dancing” and “swinging” really were, but I suspect members of the Church in 1897 would be shocked and appalled that our dance prohibitions have to include encouragement not to be sexually suggestive and to avoid music that promotes Satanism. In fact, it makes me wonder when these guidelines were written: they sound so 80s.