If you've heard people trash the astrological alphabet (Aries=1st house) but still wondered, "But how do the houses get their meanings then?" this big ass infographic on the traditional origins of house meanings is for you. You'll have to zoom in to read it. Enjoy and share! 
So here are the ways astrologers figured out what houses mean without the astrological alphabet. ::Clears throat::
1) If a house is diurnal in the sky above, it relates to something intangible, of the mind/spirit. If a house is nocturnal through the Earth below, it relates to something tangible and physical, of body/matter.
2) The angles of the Sun's daily journey are essentially equated with a life cycle, from conception in the 4th, to birth in the 1st, to the height of life in the 10th, to death in the 7th, etc.
3) Each angle is a strong house, central and angular to one's life. Each succedent house is stable house, things which are more constant throughout someone's life. Each cadent house is a weaker house, with themes less central to the narrative of one's life.
4) The cadent houses have already moved past the angle, so they signify things that happen before the event of angle. The succedent houses have yet to move past the angle, so they signify things that happen after the event of the angle.
5) Each house that makes a whole sign aspect to the rising sign is considered a "good" sign, productive or life-supporting. The houses that don't are considered "bad" signs, unconnected to what supports life.
6) The order of the signs themselves do bear relationships to the houses, but the correlations begin from the lights rather than the beginning of the zodiac. This is called the Thema Mundi. The planets in the houses of the Thema Mundi and the rulers of the empty houses matter.
7a) Planetary exaltations are signs which embody each planet's diurnal/nocturnal and benefic/malefic nature relative to their domiciles, but only within the horizonal reference of the Thema Mundi so that all exaltations are in good houses, making a whole sign aspect with Cancer.
7b) Exaltations are therefore a blend of planetary, zodiacal and horizonal concepts, and are therefore relevant to the interpretation of houses.
8) The planetary Joys are houses which match each planet's diurnal/nocturnal and benefic/malefic nature, so those houses take on the nature of those planets. I explained these in detail here:
9) Finally, some significations of the houses are interpreted by their relative position to other houses, especially the opposite house. For example, the financial connotations of the 8th come from its opposition to the 2nd and being 2nd from the 7th (for a partner's finances).
The houses bring together so many different fundamental astrological concepts, on planetary natures, sect, benefic and malefic natures, aspects, etc. I hope you'll agree this is a bit more satisfying and explanatory than "Aries=1st House".
